ARTICLE | doi:10.20944/preprints202305.0521.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: Aircraft; Wastewater; Surveillance; Indicator viruses; Enteric viruses; Respiratory viruses
Online: 8 May 2023 (10:39:58 CEST)
The effective detection of viruses in aircraft wastewater is crucial to establish surveillance programs for monitoring virus spread via aircraft passengers. This study aimed to compare the performance of two virus concentration workflows, adsorption-extraction (AE) and Nanotrap® Microbiome A Particles (NMAP), in detecting the prevalence and concentrations of 15 endogenous viruses in aircraft lavatory wastewater samples. The viruses tested include two indicator viruses, four enteric viruses, and nine respiratory viruses. The results showed that cross-assembly phage (crAssphage), human polyomavirus (HPyV), rhinovirus A (RhV A), and rhinovirus B (RhV B) were detected in all wastewater samples using both workflows. However, enterovirus (EV), human norovirus (HNoV GII), human adenovirus (HAdV), bocavirus (BoV), parechovirus (PeV), epstein-barr virus (EBV), influenza A virus (IAV), and respiratory syncytial virus B (RsV B) were infrequently detected by both workflows, and hepatitis A virus (HAV), influenza B virus (IBV), and respiratory syncytial virus B (RsV A) were not detected in any samples. The NMAP workflow had greater detection rates of EV, PeV, and RsV B than the AE workflow, while the AE workflow had greater detection rates of HAdV, BoV, and EBV than the NMAP workflow. The concentration of each virus was also analyzed, and the results showed that CrAssphage had the highest mean concentration (6.76 log10 GC/12.5 mL) followed by HPyV (5.46 log10 GC/12.5 mL using the AE workflow, while the mean concentrations of enteric and respiratory viruses ranged from 2.48 to 3.63 log10 GC/12.5 mL. Using the NMAP workflow, the mean concentration of crAssphage was 5.18 log10 GC/12.5 mL and the mean concentration of HPyV was 4.20 log10 GC/12.5 mL, while mean concentrations of enteric and respiratory viruses ranged from 2.55 to 3.74 log10 GC/12.5 mL. The mean concentrations of CrAssphage, HPyV, RhV A, and RhV B between the two workflows were statistically significant (p < 0.05). In summary, the present study provides valuable insights into the performance of virus concentration workflows in detecting and quantifying different viruses in aircraft lavatory wastewater samples. The findings can aid in the selection of an appropriate concentration workflow for virus surveillance studies and contribute to the development of efficient and reliable virus detection methods.
ARTICLE | doi:10.20944/preprints202209.0456.v1
Subject: Biology And Life Sciences, Virology Keywords: Marnaviridae; algal bloom; algal viruses; icosahedral viruses; ssRNA viruses
Online: 29 September 2022 (07:53:23 CEST)
Marnaviridae viruses are abundant algal viruses that regulate the dynamics of algal blooms in aquatic environments. They employ a narrow host range because they merely lyse their own algal host species. This host-specific lysis is thought to correspond to the unique transmission mechanism of the Marnaviridae viruses. Here, we present the atomic structures of the full and empty capsids of Chaetoceros socialis forma radians RNA virus 1 built in 3.0 Å and 3.1 Å cryo-electron microscopy maps. The empty capsid structure and the structural variability provide insights on its assembly and uncoating intermediates. In conjunction with the previously reported atomic model of the Chaetoceros tenuissimus RNA virus type II capsid, we have identified the common and diverse structural features of the VP1 surface between the Marnaviridae viruses. We have also tested the potential usage of AlphaFold2 for structural prediction of the VP1s and a subsequent structural phylogeny for classifying Marnaviridae viruses by their hosts. These findings will be crucial for inferring the host-specific transmission mechanism in Marnaviridae viruses, which is decisive for monitoring and possibly regulating the occurrence and disappearance of algae blooms.
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Leishmania; Leishmania viruses; Phylogeny; Coevolution; endosymbiont protozoan viruses
Online: 18 January 2021 (15:00:54 CET)
The description of the genus Leishmania as causative agents of leishmaniasis occurred during this modern age. But evolutionary studies suggest that the origin of Leishmania can be traced back to the Mesozoic era. Subsequently, during its evolutionary process, it sustained a worldwide dispersion predating the breakup of the Gondwana supercontinent. It is assumed that this parasite evolved from monoxenic Trypanosomatidae. Phylogenetic studies locate the dixenous Leishmania in a well-supported clade, recently named subfamily Leishmaniinae, which includes also monoxenous trypanosomatids. Virus-Like Particles were reported in many species of this family. So far, several Leishmania species have been reported as infected by Leishmania RNA Virus (LRV) and Leishbunyavirus (LBV). Since the first descriptions of LRV decades ago, differences in its genomic structure have been highlighted, leading to the designation of a LRV1 in L. (Viannia) species and a LRV2 in other L. (Leishmania) species. There are strong indications of virus infecting Leishmania spp. ability to enhance parasitic survival both in human and experimental infections, through highly complex and specialized mechanisms. Phylogenetic analyzes of these viruses have shown that their genomic differences correlate with the infected parasite species, suggesting a coevolutionary process. Herein, we will present unpublished results regarding the relationship Leishmania – endosymbiotic Leishmania viruses and will explore what has been described in the literature, and what is known about this association that could contribute to discussions about the worldwide dispersion of Leishmania.
REVIEW | doi:10.20944/preprints202111.0385.v1
Subject: Biology And Life Sciences, Virology Keywords: n/aRNA genome; Viruses; host-viruses interactions; RNA world
Online: 22 November 2021 (11:43:15 CET)
In recent years, the role of non-coding RNAs (ncRNAs) in regulating cell physiology has begun to be better understood. Recent discoveries in viral molecular biology have revealed that such cellular functions are disturbed during viral infections mainly due to host cell ncRNAs, cellular factors, and virus-derived ncRNAs. Apart from the interplay between those molecules, other interactions derive from the specific folding of RNA virus genomes. These fulfill canonical regulation functions such as replication, translation, and viral packaging. In some cases, folds serve as precursors of small viral RNAs whose biogenesis is not yet clearly understood. Since ncRNAs and RNA viral genomes modulate complex molecular and cellular processes in viral infections, a new taxonomy is being proposed here overarching three main categories, considering the current information about ncRNA interactions in some well-known viral infections. The first category shows examples of host ncRNAs associated with the trigger of the immune response under viral infections. The second category describes interactions between the virus and host ncRNAs. The last category shows how the shape of the RNA viral genome is essential in processing RNAs derived from viruses. Finally, we introduce evidence of how these three categories can also work as a framework in order to organize known interactions of ncRNAs and cellular factors under DENV infection. This new taxonomy of interactions provides a comprehensive framework for organizing the ncRNA regulatory roles in the context of viral interactions and an RNA world.
HYPOTHESIS | doi:10.20944/preprints201911.0308.v1
Subject: Biology And Life Sciences, Virology Keywords: origin and evolution of viruses; DPANN archaea; Nanoarchaeum equitans; giant viruses
Online: 26 November 2019 (04:43:45 CET)
A recent report in PNAS that Candidatus Nanohaloarchaeum antarcticus requires haloarchaeon Halorubrum lacusprofundi for growth expands the list of known symbiotic or parasitic associations between the members of DPANN archaea, which are relatively small cells with reduced genomes and limited metabolic capacity, and free-living archaea. In line with previous studies addressing the enigmatic mechanism(s) for the transfer of metabolites from Ignicoccus hospitalis to Nanoarchaeum equitans, this new study presents additional evidence supporting a direct cytoplasmic connection facilitated by the fusion of parasite’s membrane with that of its host. Here I show that this novel mechanism for accessing the host resources by a membrane fusing mechanism, which eliminates the need for sophisticated multivalent transport systems, is fundamentally similar to that employed by several viral lineages. These new findings support an evolutionary model on the origin of incipient viral lineages from parasitic cellular lineages that started their parasitic life cycle by fusing with their host cells.
BRIEF REPORT | doi:10.20944/preprints202311.1033.v1
Subject: Public Health And Healthcare, Primary Health Care Keywords: coinfection; population; respiratory viruses.
Online: 15 November 2023 (15:49:46 CET)
The 2021/2022 influenza season was not characterised by a well-defined incidence peak. A high value of incidence was recorded in week 13, but it was still lower than in other influenza seasons. This abnormal circulation was probably due to relaxation of the COVID-19 pandemic restriction measures, which greatly reduced the circulation of respiratory-transmitted viruses, including human respiratory syncytial virus (HRSV). The symptoms of SARS-CoV-2 and influenza are quite similar, sharing the human-to-human transmission route via respiratory droplets. The aim of this study was to estimate the rate of coinfection with influenza viruses and/or HRSV in SARS-CoV-2-positive subjects (N=940) in a population of central Italy during the 2021/2022 season. A total of 54 cases of coinfection were detected during the study period, 51 cases (5.4%) of SARS-CoV-2 and influenza virus and three cases (0.3%) of SARS-CoV-2 and HRSV coinfection. These results highlight the importance of continuous monitoring of the circulation of influenza virus and other respiratory viruses in the context of the COVID-19 pandemic.
REVIEW | doi:10.20944/preprints202305.1217.v1
Online: 17 May 2023 (09:55:06 CEST)
Shrimps are under the influence of several environmental factors such as fluctuation of physical and chemical parameters of the water affected by variations in rainfall, temperature, salinity, and pH. These factors have also been identified as risk factors for shrimp disease outbreaks. Despite the high levels of production, shrimp producers suffered significant economic losses in years, mainly due to the presence of diseases that now plague the industry. In particular, viral diseases have had and will continue to have profound impact on industry growth. In response to stress such environmental or pathophysiological, cells are able to up regulating selectively the expression of a protein group known as Heat Shock Proteins (HSPs). In a recent search at the literature we observed a close relation between HSP70 with apoptotic proteins and others stress proteins such HSP60 and HSP90. Moreover, the response of shrimp to viral stress was examined, some of which are correlated to the reactions of HSP70. Thus, the aim of this review is to describe the current knowledge on the status of stress responses in shrimps, particularly HSP70 responses, triggered by viruses.
ARTICLE | doi:10.20944/preprints202002.0232.v1
Subject: Biology And Life Sciences, Virology Keywords: electromagnetic properties of viruses; terahertz sensors; label-free detection of viruses; nanotechnologies
Online: 17 February 2020 (01:56:06 CET)
Our main objective in this work was to examine the possibility of non-intrusive, label-free, detection of whole Zika viruses using terahertz signals with or without a targeting/binding oligonucleotide (aptamers). We report for the first time the use of terahertz electromagnetic waves (0.75 THz – 1.1 THz) to detect Zika viruses. The Zika/aptamer complexes showed a reproducible terahertz reflection coefficient minimum at 1.064 THz while the Zika virus’s reflection minimum was at 1.073 THz. Of different substrates we examined, the polyester petri dish provided a very low loss and excellent terahertz transmission. To increase the interaction between the terahertz signal and the sample we also used polyester microbeads coated with aptamers. We then measured the terahertz reflection from the microbeads as a function of Zika concentration. The resulting terahertz Zika sensor had sensitivity of 63 Hz/Zika and minimum detectable signal of ~ 16x103 Zika. Other substrates such as Graphene on polyethylene terephthalate (PET), 50 nm-thick gold film on polycarbonate, thin (30 um-thick) glass slide and Teflon were also examined. Graphene substrate enabled direct detection of the Zika without any aptamers.
REVIEW | doi:10.20944/preprints201904.0172.v1
Subject: Biology And Life Sciences, Virology Keywords: amebae viruses; viral evolution; protein domains; mimivirus; dsDNA viruses; translation machinery; pandoravirus; NCLDV
Online: 15 April 2019 (12:50:03 CEST)
Viruses are the most prevalent infectious agents, populating almost every ecosystem on earth. Most viruses carry only a handful of genes supporting their replication and the production of capsids. It came as a great surprise in 2003 when the first giant virus was discovered and found to have a >1Mbp genome encoding almost a thousand proteins. Following this first discovery, dozens of giant virus strains across several viral families have been reported. Here, we provide an updated quantitative and qualitative view on giant viruses and elaborate on their shared and variable features. We review the complexity of giant virus proteomes, which include functions traditionally associated only with cellular organisms. These unprecedented functions include components of the translation machinery, DNA maintenance, and metabolic enzymes. We discuss the possible underlying evolutionary processes and mechanisms that might have shaped the diversity of giant viruses and their genomes, highlighting their remarkable capacity to hijack genes and genomic sequences from their hosts and environments. This leads us to examine prominent theories regarding the origin of giant viruses. Finally, we present the emerging ecological view of giant viruses, found across widespread habitats and ecological systems, with respect to the environment and human health.
REVIEW | doi:10.20944/preprints202310.1178.v1
Subject: Biology And Life Sciences, Virology Keywords: nuclear bodies; cajal bodies; PML bodies; nucleolus; snRNPs; animal viruses; plant viruses; nuclear remodelling
Online: 18 October 2023 (11:46:56 CEST)
Nuclear bodies (NBs) are dynamic structures present in eukaryotic cell nuclei. They are not bounded by membranes and are often considered biomolecular condensates, defined structurally and functionally by the localisation of core components. Nuclear architecture can be reorganised during normal cellular processes such as the cell cycle as well as in response to cellular stress. Many plant and animal viruses target their proteins to NBs, in some cases triggering their structural disruption and redistribution. Although not all such interactions have been well characterised, subversion of NBs and their functions may form a key part of the life cycle of eukaryotic viruses that require the nucleus for their replication. This review will focus on Cajal bodies (CBs) and the viruses that target them. Since CBs are dynamic structures, other NBs (principally nucleoli and promyelocytic leukaemia, PML, bodies), whose components interact with CBs, will also be considered. As well as providing important insights into key virus: host cell interactions, studies on Cajal and associated NBs may identify novel cellular targets for development of anti-viral compounds.
ARTICLE | doi:10.20944/preprints201703.0211.v2
Subject: Biology And Life Sciences, Virology Keywords: Zika virus; Flavivirus; RNA Viruses; Viruses; surveillance; occurrence; epidemiology; West Nile virus; Aedes; Culicidae
Online: 30 March 2017 (04:53:34 CEST)
In 2015 in Brazil, Zika virus showed features of geographic expansion and potentially increased virulence. In 2016, New York State issued emergency regulations after the World Health Organization declared Zika virus a Public Health Emergency of International Concern. In this study, mosquito surveillance was conducted in Westchester County, New York, to identify Zika virus and other arboviruses. Twenty trap sites were used for surveillance of Aedes albopictus mosquitoes, the Zika virus vector. The Westchester County Department of Health performed testing for Zika, West Nile, Eastern equine encephalitis, and other flaviviruses on 369 batches comprising 8,891 mosquitoes. Aedes albopictus mosquitoes were identified in Nassau, Rockland, Suffolk, Westchester, and New York City. Despite the increased capacity for specimen analysis, Zika virus was not detected. This study provides the first evidence of appropriate Zika virus surveillance. However, the results do not allow determination of the potential mechanism of local vector-to-human transmission of Zika virus among Aedes albopictus mosquitoes. This study adds to the evidence regarding the distribution, emergence, and trapping capabilities of potential Zika virus vectors.
ARTICLE | doi:10.20944/preprints202309.1161.v1
Subject: Medicine And Pharmacology, Epidemiology And Infectious Diseases Keywords: COPD; respiratory; viruses; rhinovirus; Middle East
Online: 18 September 2023 (14:50:16 CEST)
Purpose: This study aimed to describe the molecular epidemiology and seasonality of human rhinovirus (HRV) in chronic obstructive pulmonary disease (COPD) and its association with COPD exacerbations in Abu Dhabi, the United Arab Emirates (UAE). Methods: Sputum specimens were collected for analysis from all COPD patients who visited a medical center from November 2021 to October 2022. The real-time quantitative polymerase chain reaction (qPCR) test was used to detect HRV. Results: Of the 78 COPD patients included in the study, 58 (74%) pa-tients presented with one or more exacerbation episodes. The incidence of COPD exacerbation peaked over the winter and substantially decreased during the summer. HRV positivity in pa-tients during exacerbation (E1) was 11/58 (19%) and 15/58 (26%) two weeks after the exacerbation episode (E2). There was no significant difference in the HRV load in these patients. No statistically significant difference was observed in the detection of HRV during exacerbation compared to patients with stable COPD. Conclusion: This is the first study to assess the association between HRV detection by qPCR and COPD exacerbations in the UAE. The high sensitivity of the detec-tion technology helped collect reliable epidemiologic data. Few studies have provided similar Middle East data. This study's pattern of COPD exacerbations and HRV detection parallels that of temperate countries. This information can help with future, more extensive surveillance of res-piratory viruses in the UAE and the Middle East and their association with COPD exacerbations.
REVIEW | doi:10.20944/preprints202012.0239.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: glioblastoma; high-grade glioma; refractory glioma; virotherapy; oncolytic viruses; neuro-oncology; refractory glioblastoma; chimeric viruses; clinical trials
Online: 9 December 2020 (20:13:56 CET)
As new treatment modalities are being explored in neuro-oncology, viruses are emerging as a promising class of therapeutics. Virotherapy consists of introduction of either wild-type or engineered viruses to the site of disease, where they exert anti-tumor effect. These viruses can either be non-lytic, in which case they are used to deliver gene therapy, or lytic, which induce tumor cell lysis and subsequent host immunologic response. Replication-competent viruses can then go on to further infect and lyse neighboring glioma cells. This treatment paradigm is being explored extensively in both preclinical and clinical studies for a variety of indications. Virus-based therapies are advantageous due to the natural susceptibility of glioma cells to viral infection, which improves therapeutic selectivity. Furthermore, lytic viruses expose glioma antigens to the host immune system and subsequently stimulate an immune response that specifically targets tumor cells. This review surveys the current landscape of oncolytic virotherapy clinical trials in high-grade glioma, summarizes preclinical experiences, identifies challenges associated with this modality across multiple trials, and highlights potential to integrate this therapeutic strategy into promising combinatory approaches.
ARTICLE | doi:10.20944/preprints202308.1489.v1
Subject: Medicine And Pharmacology, Epidemiology And Infectious Diseases Keywords: COVID-19; Rhabdomyolisys; Viruses; SARS-COV-2
Online: 22 August 2023 (07:36:29 CEST)
Rhabdomyolysis is a serious clinical condition, which if left untreated can lead to kidney failure and in extreme cases, to death. It has also been reported in association with SARS COV2 infection and can be its initial presentation. COVID-19 is a disease caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2), which has many variants that change the characteristics of the disease affecting, among other things, the method of transmission or treatment. Some investigators have implicated excessive immune response in the causes of muscle damage during SARS-CoV-2 infection. Others point to direct damage caused by the virus or involving immune factors. In this study we described cases of COVID-19 infection from 1 June 2022 to 15 July 2022 with elevated muscle enzymes in the blood and hospitalized to the first division of Cotugno hospital in Campania. Of 39 patients with SARS-CoV-2 infection, 15 patients presented also rhabdomyolysis. The most common symptoms were: asthenia, fever, arthomyalgia, lipothymia and syncope. No patient had myocardial infarction and 2 patients had atrial fibrillation. All patients were affected by omicron SARS-CoV-2 variants. Of these patients: 4 patients died (2 due to rhabdomyolysis and 2 due to sepsis) and only one patient presented acute kidney injury.
REVIEW | doi:10.20944/preprints202307.0824.v1
Subject: Biology And Life Sciences, Virology Keywords: databases; viruses; genomees; sequences; metadata; FAIR evaluation
Online: 12 July 2023 (12:21:15 CEST)
Viruses are abundant and diverse entities that have important roles in public health, ecology, and agriculture. Identification and surveillance of viruses rely on understanding their genome organization, sequences, and replication strategy. Despite technological advancements in sequencing methods, our current understanding of virus diversity remains incomplete, highlighting the need to explore undiscovered viruses. Virus databases play a crucial role in providing access to sequences, annotations and other metadata, and analysis tools for studying viruses. However, there has not been a comprehensive review of virus databases in the last five years. This study aimed to fill this gap by identifying 24 active virus databases and included an extensive evaluation of their content, functionality and compliance with the FAIR principles. In this study, we thoroughly assessed the search capabilities of five database catalogs, which serve as comprehensive repositories housing a diverse array of databases and offering essential metadata. Moreover, we conducted a comprehensive review of different types of errors, encompassing taxonomy, names, missing information, sequences, sequence orientation, and chimeric sequences, with the intention of empowering users to effectively tackle these challenges. We expect this review to aid users in selecting suitable virus databases and other resources, and to help databases in error management and improve their adherence to the FAIR principles. The databases listed here represent current knowledge of viruses and will help aid users find databases of interest based on content, functionality, and scope. Use of virus databases is integral to gain new insights into the biology, evolution, and transmission of viruses, and develop new strategies to manage virus outbreaks and preserve global health.
REVIEW | doi:10.20944/preprints202208.0204.v1
Subject: Biology And Life Sciences, Virology Keywords: Vaccine cocktail; COVID-19; MERS; SARS; Viruses
Online: 11 August 2022 (03:22:22 CEST)
Severe Acute Respiratory Syndrome Coronavirus 2 commonly known as SARS-CoV-2 is the utmost challenging pandemic that attracted scientific community to discover therapeutics as well as vaccination solutions to control SARS-CoV-2. Different diagnostic and detection methods have been improved and re-introduced from the previous observations of SERS and MERS. Due to the high mortality rate and fast spread, researchers all around the globe gathered to develop an effective vaccine. The review article summarizes various types of vaccines, mutants of virus, strategies in tackling virus, vaccine development and its global distribution with the focus on the use of mix and match of vaccines to fight the virus. The reported studies depict the design and production of successful COVID-19 vaccines with good efficacy as the selected vaccine population embrace high-risk personages i.e. above the age of 60, frontline workers and other essential service workers. We have targeted at delivering an outline of the determinations devoted to an effectual vaccine for novel Covid-19 that has restricted the domain by means of human health, economy, as well as life.
REVIEW | doi:10.20944/preprints202207.0075.v1
Subject: Biology And Life Sciences, Virology Keywords: monkeypox; zoonosis; emerging viruses; 2022 MPX outbreak
Online: 5 July 2022 (13:43:09 CEST)
The global vaccination programme against smallpox (SPX) led to its successful eradication and averted millions of deaths. Monkeypox (MPX) is a close relative of SPX. Due to their antigenic similarity, SPX vaccines cross-protect against MPX. However, over 70% of people living today were never vaccinated. Symptoms of MPX infection include fever, head and muscle ache, lymphadenopathy and a characteristic rash that develops into papules, vesicles and pustules which eventually scab over and heal. MPX is less often fatal (case fatality rates range from less than 1% to up to 11%) than SPX (up to 30%). MPX is endemic in sub-Saharan Africa, infecting wild animals and causing zoonotic outbreaks. Exotic animal trade and international travel combined with the increasing susceptibility of the human population due to halted vaccination facilitated the spread of MPX to new areas. The ongoing outbreak with over 6500 confirmed cases in >50 countries between May and July 2022 shows that MPX can significantly spread between people, and may thus become a serious threat to public health with global consequences. Here, we summarize the current knowledge about this re-emerging virus, discuss available strategies to limit its spread and pathogenicity and evaluate its risk to the human population.
ARTICLE | doi:10.20944/preprints202106.0410.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: highly pathogenic avian influenza viruses, pathogenicity factors.
Online: 15 June 2021 (14:29:26 CEST)
The H7 subtype of avian influenza viruses (AIV) stands out among other AIV. The H7 viruses cir-culate in ducks, poultry, equine and have repeatedly caused outbreaks of disease in humans. In or-der to study the pathogenicity factors of H7N1 viruses, several variants were obtained, starting with laboratory strain, with a history of 12 passages through chicken embryos. This strain, A/chicken/Rostock/R0p/1934(H7N1) (R0p) had only 3 substitution in HA relatively A/Chicken/Rostock/45/34(H7N1), substitution Arg140Gly among them. 10 variants of this strain was obtained and studied to ascertain its biological property, genome stability and factors of patho-genicity. Strain R0p had decreased virulence for chicken, comparing with described in literature virulence of A/FPV Rostock/34 and A/chicken/Rostock/34 viruses. After 10 passages through the chicken lungs variant was obtained much more pathogenic than the starting R0p. The study of in-termediate passages through the chicken lungs showed that the jump in pathogenicity had occurred sharply between the fifth and sixth passage. By cloning these variants, a pair of strains (R5p and R6p) were obtained, and the complete genomes of these strains were sequenced. Single amino acid substitution was revealed, namely reversion Gly140Arg in HA1. This amino acid is located at the head part of the hemagglutinin, adjacent to the receptor-binding site. In addition to the increased pathogenicity for chicken and mice, R6p differs from R5p in the pattern of foci in cell culture and an increased affinity for a negatively charged receptor analogue, while maintaining a pattern of recep-tor binding specificity and the pH optimum of the HA conformational change.
Subject: Biology And Life Sciences, Virology Keywords: highly pathogenic avian influenza viruses, pathogenicity factors.
Online: 10 May 2021 (14:22:23 CEST)
The H7 subtype of avian influenza viruses (AIV) stands out among other AIV. H7 viruses circulate in ducks, poultry, equine and have repeatedly caused outbreaks of disease in humans. In order to study the pathogenicity factors of H7N1 viruses, several laboratory variants of the A/FPV/Rostock/34 (H7N1) strain were obtained by passages in the chicken lungs. After 10 such passages, a variant was obtained that differed from the parent virus by amino acid substitutions Val109Phe in PB2, Gln621Lys in PB1, Thr32Ala and Leu586Phe in PA Gly140Arg in HA1 and Ala101Thr in HA2 (numbering by H3), Ser82Arg in M2, Arg118Lys and Met124Arg in NS1. No differences were found in proteins NA, NP, M1 and NS2. The resulting variant was hundreds of times more pathogenic for chickens than the original laboratory variant of the virus. The study of intermediate passages showed that the jump in pathogenicity occurs sharply between the fifth and sixth passage through the chicken lungs. By cloning these variants, a pair of strains (R5p and R6p) were obtained, and the complete genomes of these strains were sequenced. Single amino acid substitution was revealed, namely Gly140Arg in HA1. It is important to emphasize that this substitution is a reversion, since Arg is located in position 140 HA1 of original the A/FPV/Rostock/34 (H7N1) virus (GenBank). This amino acid is located at the head part of the hemagglutinin, adjacent to the receptor-binding site. In addition to the increased pathogenicity, R6p differs from R5p by an increased affinity for a negatively charged receptor analogue, an increased affinity for MDCK cells, while maintaining a receptor specificity profile.
REVIEW | doi:10.20944/preprints201911.0320.v1
Subject: Biology And Life Sciences, Virology Keywords: herpesviruses; oncogenic viruses; head and neck cancer
Online: 26 November 2019 (15:28:52 CET)
Head and neck cancers arise from mucosa lining the oral cavity, oropharynx, hypopharynx, larynx, sinonasal tract, and nasopharynx and the etiology of head and neck cancers is complex and involves many factors, among which oncogenic viruses are also enumerated. Nevertheless, this type of cancers are among the most common cancers around the world. The thorough knowledge of the pathogenesis of viral infection is needed to fully understand its impact on cancer development.
ARTICLE | doi:10.20944/preprints201810.0201.v1
Subject: Medicine And Pharmacology, Gastroenterology And Hepatology Keywords: hepatitis c viruses; hepatitis e virus; dentists
Online: 10 October 2018 (05:21:20 CEST)
Health care workers (HCWs), specifically dentists, are at the front line for acquiring blood-borne virus infections. The highest proportion of occupational transmission is through percutaneous injuries via hollow-bore needles. Several studies around the world have reported that hepatitis viruses and human immunodeficiency virus are the main pathogens for most cases of occupationally acquired blood-borne infection. We aim to investigate the prevalence of hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis E virus (HEV), and human immunodeficiency virus (HIV) among Mexican dentists. Methods. We included 159 dentists who attended the annual meeting at the Medica Sur Clinic & Foundation held in Mexico City in May 2016. A survey was applied in order to obtain data of occupational exposure to blood-borne viruses (BBV). Serum samples were screened serologically using enzyme-linked immunosorbent assays. Results. Two dentists (1.2%) were positive for antibodies against HCV antigen, one (0.6%) was positive for antibodies against HBV antigen and three (1.8%) were positive for the detection of IgG antibodies against HEV. Two cases (1.2%) were positive for antibodies against HIV. Conclusions. The infection by HEV was the most prevalent among dentists. However, the prevalence of BBV in dentists was similar to that in the general population.
REVIEW | doi:10.20944/preprints202308.0995.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Respiratory infection; etiology; viruses; bacteria; sub-Saharan Africa
Online: 14 August 2023 (08:44:59 CEST)
(1) Background: Respiratory infections are a major public health problem worldwide, with potentially serious consequences. Indeed, these infections remain one of the main causes of morbidity and mortality in children under 5 years old in developing countries. Etiological information on respiratory infections is crucial for prevention and case management strategies. This systematic review aims to describe the etiology of respiratory infections reported in studies carried out in sub-Saharan African countries; (2) Methods: Using PubMed, HINARI and Google scholar search engines, a systematic search was carried out to identify published articles on the etiology of viral and/or bacterial respiratory infections in sub-Saharan Africa in patients of all ages. We have only considered data from sub-Saharan Africa. Papers published from 2010 to 2021, in English or French have been included in this review; (3) Results: After reviewing 115 articles reporting studies carried out in the African continent, only 32 articles were selected of which, studies were conducted in 15 sub-Saharan African countries, including 6/32 (18.75%) in Cameroon. Twenty (62.5%) were cross-sectional studies, and twenty-four (75%) were hospital-based investigations. In these studies, RT-PCR and culture methods were respectively used for viruses and bacteria investigations. Respiratory syncytial virus was the most frequently identified, with prevalence ranging from 0.6% to 59%, followed by rhinovirus (9.3% -73%), influenza virus (flu) A/B (0.9%-69.1%), and human adenovirus (0.9% - 30.8%). Streptococcus pneumoniae (14.2% - 96%), followed by Haemophilus influenzae type b (2.5% - 54%), and Klebsiella pneumoniae (1.4% - 49.9%) were the most frequently detected bacteria; (4) Conclusions: This review has reported that many pathogens, mainly viruses, are associated with acute respiratory infections in sub-Saharan Africa in both children and adults. Unfortunately, the limited geographical distribution of data across sub-Saharan Africa does not allow most of countries to develop an effective strategy for the prevention and treatment of respiratory infections.
ARTICLE | doi:10.20944/preprints202307.1016.v1
Subject: Biology And Life Sciences, Virology Keywords: metagenomics; virome; viruses; mosquito; Novosibirsk region; Western Siberia
Online: 17 July 2023 (02:42:38 CEST)
Metagenomic analysis of mosquitoes allows the genetic characterization of mosquito-associated viruses in different regions of the world. This study applied the metagenomic approach to search for novel viral sequences in seven species of mosquitoes collected from the Novosibirsk region of Western Siberia. Using NGS sequencing, we identified 15 coding-complete viral polyproteins (genomes) and 15 viral-like partial sequences in mosquitoes. The complete sequences for novel viruses or partial sequences of capsid proteins, hypothetical viral proteins, and RdRp were used to identify their taxonomy. The novel viral sequences were classified within the orders Tymovirales and Picornavirales, the families Partitiviridae, Totiviridae, Tombusviridae, Iflaviridae, Nodaviridae, Permutotetraviridae, Solemoviridae, with several attributed to four unclassified RNA-viruses. The main part of the novel putative viruses and viral sequences was associated with Coquillettidia richardii mosquito. This study is intended to increase our understanding of viral diversity in mosquitoes found in the natural habitats of Siberia, characterized by very long, snowy, and cold winters.
REVIEW | doi:10.20944/preprints202304.0638.v1
Subject: Public Health And Healthcare, Other Keywords: dog; enteric viruses; emerging parvoviruses; protoparvoviruses; bocaparvoviruses; chaphamaparvoviruses.
Online: 20 April 2023 (09:39:49 CEST)
Parvovirus infections have been well known for around 100 years in domestic carnivores. However, the use of molecular assays and metagenomic approaches for virus discovery and characterization has led to the detection of novel parvovirus species and/or variants in dog. Although some evidence suggests that these emerging canine parvoviruses may act as primary causative agents or as synergistic pathogens in the diseases of domestic carnivores, several aspects regarding epidemiology and virus-host interaction remain to be elucidated.
REVIEW | doi:10.20944/preprints202208.0236.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: Archaea; transcription inhibition; RNA polymerase; viruses; evolution; antibiotics
Online: 12 August 2022 (11:25:05 CEST)
Multisubunit RNA polymerases (RNAP) carry out transcription in all domains of life; during vi-rus infection, RNAPs are targeted by transcription factors encoded by either the cell or the virus, resulting in the global repression of transcription with distinct outcomes for different host-virus combinations. These repressors serve as versatile molecular probes to study RNAP mechanisms, as well as they aid the exploration of druggable sites for the development of new antibiotics. Here, we review the mechanisms and structural basis of RNAP inhibition by the viral repressor RIP and the crenarchaeal negative regulator TFS4, which follow distinct strategies. RIP operates by occluding the DNA-binding channel and mimicking the initiation factor TFB/TFIIB. RIP binds tightly to the clamp and locks it into one fixed position, thereby preventing conformational oscil-lations that are critical for RNAP function as it progresses through the transcription cycle. TFS4 engages with RNAP in a similar manner to transcript cleavage factors such as TFS/TFIIS through the NTP-entry channel; TFS4 interferes with the trigger loop and bridge helix within the active site by occlusion and allosteric mechanisms, respectively. The conformational changes of RNAP described above are universally conserved and are also seen in inactive dimers of eukaryotic RNAPI and several inhibited RNAP complexes of both bacterial and eukaryotic RNA polymer-ases, including inactive states that precede transcription termination. A comparison of target sites and inhibitory mechanisms reveals that proteinaceous repressors and RNAP-specific antibiotics use surprisingly common ways to inhibit RNAP function.
CONCEPT PAPER | doi:10.20944/preprints202206.0094.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: : viruses; synthetic organisms; artificial life; life domains; Lithbea
Online: 7 June 2022 (04:42:38 CEST)
As synthetic/artificial life forms become more abundant and sophisticated, an increasing number of bizarre creatures - xenobots, robots, soft A-life entities, genetically engineered organisms, etc. - are invading our society. Therefore, we need to bring order to all this, to establish what is living and what is not. Here, I intend to classify all these non-natural entities and clarify their status with reference to their consideration or not as living beings, leaving the door open to an uncertain future in which perhaps we can see how "the artificial" and "the natural" merge to originate something new. To order all this "new biodiversity" and to also give entry to viruses (which are excluded of the three-domains tree of life), I propose the creation of a new domain, Lithbea (from the name: life-in-the-border entities), in which all these new human-made entities as well as the viruses will be included. Within this domain there would be two kingdoms, Virus and Humade (contraction of human-made), based on their origin, natural or human-made. A brief description of each component of Lithbea is included and the implications for society and biology of this “new biodiversity” is briefly discussed.
REVIEW | doi:10.20944/preprints202010.0606.v1
Subject: Biology And Life Sciences, Ecology, Evolution, Behavior And Systematics Keywords: virology; emerging viruses; vector-borne diseases; climate change
Online: 29 October 2020 (09:49:40 CET)
Three decades have now passed since the first papers linking climate change to issues in human disease and healthcare. One of the most active topics in this area has been the implication of climate change events, particularly temperature and humidity fluctuations, in the northward spread of vector-borne viruses from more tropical regions into Europe and North America. However, some detailed studies of one such emerging disease, tick-borne encephalitis virus (TBEv), have called the connection into question, concentrating the debate on the investigation of precise mechanisms for the spread of viral disease. More recently, firmer statistical correlations have been made between climate variables, the presence of insect vectors and the prevalence of viral disease, particularly for West Nile Virus (WNV). These insights suggest avenues for mechanistic confirmation of the involvement of climate change in other diseases where the connection remains conjectural.
COMMUNICATION | doi:10.20944/preprints202005.0138.v1
Subject: Biology And Life Sciences, Virology Keywords: covid-19; epidemiology; epidemiological week; Brazil; coronavirus; viruses
Online: 8 May 2020 (08:08:40 CEST)
Amid the covid-19 pandemic, other diseases, including viruses, are still acting to the detriment of their seasonality and risk factors for contagion. For this reason, it is interesting to know the degree of impact of other viruses, mainly respiratory, in which they have similar symptoms, in diagnoses for contamination by the new coronavirus based on epidemiological surveys, via epidemiological weeks, in Brazil. To what extent there may be a hypothesis of confusion of contaminated data, harming the health system, with regard to the need for intensive care units and control of viruses, and negatively or positively implying in the control or uncontrolling of viruses in general.
REVIEW | doi:10.20944/preprints201906.0085.v1
Subject: Biology And Life Sciences, Virology Keywords: H9N2; avian influenza viruses; zoonotic; pandemic potential; poultry
Online: 11 June 2019 (07:44:44 CEST)
H9N2 avian influenza viruses have become globally widespread in poultry over the last two decades and represent a genuine threat both to the global poultry industry but also humans through their high rates of zoonotic infection and pandemic potential. H9N2 viruses are generally hyperendemic in effected countries and have been found in poultry in many new regions in recent years. In this review we examine the current global spread of H9N2 avian influenza viruses as well as their host range, tropism, transmission routes and the risk posed by these viruses to human health.
REVIEW | doi:10.20944/preprints202106.0526.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: virome; microbiome; next generation sequencing; mycoviruses; plant pathogenic viruses
Online: 21 June 2021 (16:23:44 CEST)
Forest health is dependent on the variability of microorganisms interacting with the host tree/holobiont. Symbiotic microbiota and pathogens engage in a permanent interplay, which influences the host. Thanks to the development of NGS technologies, a vast amount of genetic information on the virosphere of temperate forests has been gained the last seven years. To estimate the qualitative/quantitative impact of NGS in forest virology, we have summarized viruses affecting major tree/shrub species and their fungal associates, including fungal plant pathogens, mutualists and saprotrophs. The contribution of NGS methods is extremely significant for forest virology. Reviewed data about viral presence in holobionts, allowed us to address the role of the virome in the holobionts. Genetic variation is a crucial aspect in hologenome, significantly reinforced by horizontal gene transfer among all interacting actors. Through virus-virus interplays synergistic or antagonistic relations may evolve, which may drastically affect the health of the holobiont. Novel insights of these interplays may allow practical applications for forest plant protection based on endophytes and mycovirus biocontrol agents. The current analysis is conceived in light of the prospect that novel viruses may initiate an emergent infectious disease and that measures for avoidance of future outbreaks in forests should be considered.
ARTICLE | doi:10.20944/preprints202104.0072.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: T cells; protein immunodominance; cytokine polarization; influenza viruses; vaccine
Online: 2 April 2021 (14:28:32 CEST)
The role of T cell immunity has been acknowledged in recent vaccine development and evaluation. We tested the humoral and cellular immune responses to Flucelvax®, a quadrivalent inactivated seasonal influenza vaccine containing two influenza A (H1N1 Singapore/GP1908/2015 IVR-180 and H3N2 North Carolina/04/2016) and two influenza B (Iowa/06/2017 and Singapore/INFTT-16-0610/2016) virus strains, using peripheral blood mononuclear cells stimulated by pools of peptides overlapping all the individual influenza viral protein components. Baseline reactivity was detected against all four strains both at the level of CD4 and CD8 responses and targeting different proteins. CD4 T cell reactivity was mostly directed to HA/NA proteins in influenza B strains, and NP/M1/M2/NS1/NEP proteins in the case of the Influenza A strains. CD8 responses to both influenza A and B viruses preferentially targeted the more conserved core viral proteins. Following vaccination, both CD4 and CD8 responses against the various influenza antigens were increased in day 15 to day 91 post vaccination period and maintained a Th1 polarized profile. Importantly, no vaccine interference was detected, with the increased responses balanced across all 4 included viral strains for both CD4 and CD8 T cells, and targeting HA and multiple additional viral antigens.
BRIEF REPORT | doi:10.20944/preprints202101.0416.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Respiratory Syncytial Virus, Molecular Diagnostic, Respiratory Viruses, Coronavirus, Bronchiolitis
Online: 21 January 2021 (12:12:25 CET)
Over two years (2012-2014), 719 nasopharyngeal samples were collected from 6 weeks to 12 months old infants presenting at emergency department with moderate to severe acute bronchiolitis. Viral testing was performed and we found 98% positive samples including 90% Respiratory Syncytial Virus, 34% Human Rhino Virus, and 55% viral co-detections with predominance of RSV/HRV co-infections (30%). Interestingly, we found that the risk of being infected by HRV is higher in the absence of RSV, suggesting interferences or exclusion mechanisms between these two viruses. Conversely, Coronavirus infection had no impact on the likelihood of co-infection involving HRV and RSV. Bronchiolitis is the leading cause of hospitalizations in infants before 12 months of age, and many questions about its role in the later chronic respiratory diseases (asthma and chronic obstructive pulmonary disease) do exist. Role of virus detection and burden of viral codetections need to be further explored, in order to understand the physiopathology of chronic respiratory diseases, a major public health issue.
ARTICLE | doi:10.20944/preprints202311.0101.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: human blood sera; seasonal flu; influenza viruses with pandemic potential
Online: 2 November 2023 (07:18:53 CET)
This paper presents a study of human blood sera samples, collected in various regions of the Russian Federation, with regard to both vaccine and pandemic avian influenza viral strains. Just before the 2022-2023 epidemic season, herd immunity to seasonal influenza A viruses was reportedly lower than before the COVID-19 pandemic. Since no stable circulation of A/H5Nx and A/H9N2 influenza in the human population was observed during this period, we believe 100% vaccination against seasonal influenza is necessary for employees of poultry farms and other organizations, closely connected to the breeding and processing of poultry. In addition to protection against seasonal influenza, vaccination can hamper the emergence of new viral variants, driven by genome reassortment, during simultaneous infection of humans with seasonal human and animal influenza viruses.
REVIEW | doi:10.20944/preprints202305.0906.v2
Subject: Biology And Life Sciences, Virology Keywords: Respiratory viruses; Anosmia; Olfaction Disorders; loss of smell; Covid-19
Online: 16 October 2023 (08:54:50 CEST)
Acute respiratory viruses (ARVs) are leading cause of diseases in human worldwide. High risk individuals including children and elderly could potentially develop severe illness that could result in hospitalization or death in the worst case. Most common ARVs are Human respiratory syncytial virus, Human Metapneumovirus, Human Parainfluenza Virus, rhinovirus, coronaviruses (including SARS and MERS CoV), adenoviruses, Human Bocavirus, enterovirus (-D68 and 71), and influenza viruses. The olfactory deficits due to ARVs infection is a common symptom among patients. This mini review provides an overview of the role of SARS-CoV-2 and other common ARVs in the development of human olfactory pathophysiology. We highlight the critical need for understanding the signaling underlying the olfactory dysfunction and the development of therapeutics for this wide-ranging category of AVRs to restore the altered or loss of smell in affected patients.
ARTICLE | doi:10.20944/preprints202304.1111.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: viruses; SARS-CoV-2; Raman spectroscopy; magnetic beads; sample preparation
Online: 28 April 2023 (04:46:10 CEST)
We introduce a magnetic bead-based sample preparation scheme for enabling a Raman spectroscopic differentiation of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) positive and negative samples. The beads were functionalized with the angiotensin-converting enzyme 2 (ACE2) receptor protein, which is used as recognition element to selectively enrich SARS-CoV-2 on the surface of the magnetic beads. Subsequent Raman measurements directly enable discriminating SARS-CoV-2 positive and negative samples. The proposed approach is applicable for other virus species, too, when the specific recognition element is exchanged. Series of Raman spectra were measured on three types of samples, namely SARS-CoV-2, Influenza A H1N1 virus and a negative control. For each sample type, eight independent replicates were considered. All spectra are dominated by the magnetic bead substrate and no obvious differences between sample types are apparent. In order to address the subtle differences in the spectra, we calculated different correlation coefficients, namely the Pearson coefficient and the Normalized Cross Correlation coefficient. By comparing the correlation with the negative control differentiating between SARS-CoV-2 and Influenza A virus is possible. This study provides a first step towards the detection and potential classification of different viruses with the use of conventional Raman spectroscopy.
ARTICLE | doi:10.20944/preprints202105.0206.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: Simian Immunodeficiency Virus; SIVmac239; barcoded viruses; intravenous challenge; intrarectal challenge
Online: 10 May 2021 (15:01:31 CEST)
Little is known about how individual virus lineages replicating during acute Human Immunodeficiency Virus or Simian Immunodeficiency Virus (HIV/SIV) infection persist into chronic infection. In this study, we use molecularly barcoded SIV (SIVmac239M) to track distinct viral lineages for 12 weeks after intravenous and intrarectal challenge in macaques. Two Mafa-A1*063+ cynomolgus macaques (Macaca fascicularis) were challenged intravenously (IV), and two Mamu-A1*001+ rhesus macaques (Macaca mulatta) were challenged intrarectally (IR) with 200,000 Infectious Units (IU) of SIVmac239M. We deep sequenced the molecular barcode from all animals over 12 weeks to characterize the diversity and persistence of virus lineages, as well as the sequences of T cell epitopes during acute SIV infection. During the first three weeks post-infection, we found ~175-950 times more unique virus lineages circulating in the animals challenged intravenously than those challenged intrarectally, suggesting that challenge route is the primary driver restricting the transmission of individual viral lineages. Additionally, the emergence of escape variants can occur on multiple virus templates simultaneously, but elimination of some templates is likely a consequence of additional host factors. These data imply that virus lineages present during acute infection can be eliminated from the virus population even after initial T cell selection.
ARTICLE | doi:10.20944/preprints202103.0696.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: extracellular vesicles; enveloped viruses; lentiviral vectors; exosome; proteomic; lipidomic; transcriptomic
Online: 29 March 2021 (13:53:53 CEST)
Lentiviral vectors (LVs) are a powerful tool for gene and cell therapy and human embryonic kidney cells (HEK293) have been extensively used as a platform for production of these vectors. Like most cells and cellular tissues, HEK293 cells release extracellular vesicles (EVs). EVs released by cells share similar size, biophysical characteristics and even a biogenesis pathway with cell-produced enveloped viruses, making it a challenge to efficiently separate EVs from LVs. Thus, EVs co-purify with LVs during downstream processing, becoming “impurities” in the context of cell therapy. To characterize EVs from an inducible lentivirus producing cell line, two conditions were studied: non-induced and induced. EVs’ identity was confirmed by transmission electron microscopy and western blot. Seven proteins were identified by mass spectrometry as potential EV markers. Lipid composition of EVs and LVs showed similar enrichment in phosphatidylserine. RNA cargos in EVs showed enrichment in genes involved in viral processes and binding functions. Flow virometry, GTA and ddPCR results also confirmed the heterogenic nature of EVs and LVs populations. These findings provide insights on the product profile of lentiviral preparation and could help develop separation strategies of co-produced EVs.
ARTICLE | doi:10.20944/preprints202012.0258.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: co-infection; SARS-CoV-2; Covid-19; seasonal respiratory viruses
Online: 10 December 2020 (12:53:28 CET)
Background: Co-infections of SARS-CoV-2 with respiratory viruses, bacteria and fungi have been reported to cause a wide range of illness. Objectives: We asses s the prevalence of co-infection of SARS-CoV-2 with seasonal respiratory viruses, document the respiratory viruses detected among individuals tested for SARS-CoV-2, and describe characteristics of individuals with respiratory virus co-infection detected. Methods: Specimens included in this study were submitted as part of routine clinical testing to Public Health Ontario Laboratory from individuals requiring testing for SARS-CoV-2 and/or seasonal respiratory viruses. Results: Co-infection was detected in a smaller proportion (2.5%) of individuals with laboratory confirmed SARS-CoV-2 than those with seasonal respiratory viruses (4.3%); this difference was not significant. Individuals with any respiratory virus co-infection were more likely to be younger than 65 years of age and male than those with single infection. Those with SARS-CoV-2 co-infection manifested mostly mild respiratory symptoms. Conclusions: Findings of this study may not support routine testing for seasonal respiratory viruses among all individuals tested for SARS-CoV-2, as they were rare during the study period nor associated with severe disease. However, testing for seasonal respiratory viruses should be performed in severely ill individuals, in which detection of other viruses may assist with patient management.
ARTICLE | doi:10.20944/preprints201804.0151.v1
Subject: Medicine And Pharmacology, Pathology And Pathobiology Keywords: Cervical cancer – viruses – Human Papillomaviruses – Epstein-Barr virus – Id-1
Online: 11 April 2018 (13:49:57 CEST)
Epstein–Barr virus (EBV) has been recently shown to be co-present with high-risk human papillomaviruses (HPVs) in human cervical cancer; thus, these oncoviruses play an important role in the initiation and/or progression of this cancer. Accordingly, our group has recently viewed the presence and genotyping distribution of high-risk HPVs in cervical cancer in Syrian women; our data pointed out that HPVs are present in 95.45% of our samples. Herein, we aim to explore the co-prevalence of EBV and high-risk HPVs in 44 cervical cancer tissues from Syrian women using polymerase chain reaction (PCR), immunohistochemistry (IHC) and tissue microarray (TMA) analyses. We found that EBV and high-risk HPVs are co-present in 15/44 (34%) of the samples. Additionally, we report that the co-expression of LMP1 and E6 genes of EBV and high-risk HPVs, respectively, is associated with poorly differentiated squamous cell carcinomas phenotype; this is accompanied by a strong and diffused Id-1 overexpression, which is an important regulator of cell invasion and metastasis. These data imply that EBV and HPVs are co-present in cervical cancer in the Middle East area including Syria and their co-presence is associated with a more aggressive cancer phenotype. Future investigations are needed to elucidate the exact role of EBV and HPVs cooperation in cervical carcinogenesis.
REVIEW | doi:10.20944/preprints202009.0361.v2
Subject: Biology And Life Sciences, Virology Keywords: SARS-CoV-2; COVID-19; foodborne viruses; enteric viruses; fecal-oral transmission; fresh produce, berries, fruits, hepatitis A virus, Norovirus, ready-to-eat foods.
Online: 18 September 2020 (10:35:33 CEST)
Background:Although highly strict social distancing and viral spread protection guidelines are in force, the reported numbers of COVID-19 cases across the world are still increasing. This indicates that we are still unable to completely understand the transmission routes of SARS-CoV-2. One of the possible routes that can play a significant role is the fecal-oral transmission since SARS-CoV-2 can replicate in the intestines as demonstrated by isolation of infectious virus from fecal samples of COVID-19 cases. Scope and approach:In this review, we compare the characteristics of SARS-CoV-2 with the distinctive characteristics of enteric foodborne viruses. We also discuss and respond to the arguments given in some reports that downplay the importance of foodborne transmission route of SARS-CoV-2. Key findings and conclusions:Enteric viruses such as human noroviruses (HuNoVs) and hepatitis A virus (HAV) are known to transmit through foods such as fresh produce and berries, leading to frequent multistate foodborne disease outbreaks all over the world. SARS-CoV-2 was found to share four distinctive characteristics of foodborne viruses that allow them to transmit through foods. This similarity in characteristics, recent report of detecting SARS-CoV-2 particles from frozen food packages in China, and recent suspected foodborne COVID-19 case in New Zealand, indicate that foodborne transmission of SARS-CoV-2 is more evident than previously thought possible. To support or deny this route of transmission, urgent research needs to be undertaken to answer two primary questions and many secondary ones as described in this review.
Subject: Biology And Life Sciences, Virology Keywords: pandemics; contagious diseases; human race extinction; viruses; microbiome; COVID-19; blindness
Online: 14 April 2021 (17:53:49 CEST)
The recent SARS-CoV-2 pandemic, which is causing COVID 19 disease, has taught us unexpected lessons about the dangers of human extinction through highly contagious and lethal diseases. As the COVID 19 pandemic is now being controlled by various isolation measures, therapeutics and vaccines, it became clear that our current lifestyle and societal functions may not be sustainable in the long term. We now have to start thinking and planning on how to face the next dangerous pandemic, not just overcoming the one that is upon us now. Is there any evidence that even worse pandemics could strike us in the near future and threaten the existence of the human race? The answer is unequivocally yes. It is not necessary to get infected by viruses of bats, pangolins and other exotic animals that live in remote forests in order to be in danger. Creditable scientific evidence indicates that the human gut microbiota harbor billions of viruses which are capable of affecting the function of vital human organs such as the immune system, lung, brain, liver, kidney, heart etc. It is possible that the development of pathogenic variants in the gut can lead to contagious viruses which can cause pandemics, leading to destruction of vital organs, causing death or various debilitating diseases such as blindness, respiratory, liver, heart and kidney failures. These diseases could result n the complete shutdown of our civilization and probably the extinction of human race. In this essay, I will first provide a few independent pieces of scientific facts and then combine this information to come up with some (but certainly not all) hypothetical scenarios that could cause human race misery, even extinction. I hope that these scary scenarios will trigger preventative measures that could reverse or delay the projected adverse outcomes.
CONCEPT PAPER | doi:10.20944/preprints202008.0661.v1
Subject: Biology And Life Sciences, Virology Keywords: life definition; living being definition; robot definition; living viruses; extraterrestrial life
Online: 30 August 2020 (11:33:48 CEST)
What is life, what is the difference between something that is alive and something that is not, are viruses living beings, or what would life be like elsewhere in the universe, are questions that still do not have clear-cut answers fully accepted by the scientific community. Based on the fundamental attributes of all living things, I define life as a process that takes place in very ordered organic structures and is characterized by being automatic, interactive and evolutionary. I also define a living being as an organic, highly ordered, automatic, interacting and evolutionary system, and a robot as an ordered automatic and interacting system. Based on this definition and what we know about the biology of viruses, I maintain that they should be considered as living entities. Finally, I explain why if there were life elsewhere in the universe, it would be very similar to what we know on our planet.
REVIEW | doi:10.20944/preprints202004.0080.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: cancer-related viruses; CRISPR-Cas diagnostic tools; DETECTR; infectious disease; SHERLOCKv2
Online: 7 April 2020 (09:43:22 CEST)
Sensitive and precise nucleic acid detection is critical for clinical diagnostics and biotechnological advancements. Diagnostic in infectious disease field is very unique from diagnosing any other disease, that is time is of the essence; in outbreaks people die even with each passing hour in some cases, if the correct diagnosis wasn't make; for example Zika in particularly is a very challenging virus to diagnose, because it's in very few numbers of copies in the infected person, so it need high sensitive diagnostic approach to spot it, In particular, the advanced tools SHERLOCKv2 and DETECTR, give almost an immediate detection of attomolar amounts of pathogenic nucleic acids with specificity similar to that of PCR but with slight technical settings and that will guide the correct intervention for the patient. SHERLOCKv2 and DETECTR technologies are game changers for our ability to identify infectious disease and rapid detection of tumor DNA or cancer-related viruses with ultra-sensitive tests that don’t require a lot of complicated processing to go through. In this paper, we will review cutting-edge infectious disease diagnosis by CRISPR-Cas systems.
ARTICLE | doi:10.20944/preprints202305.0869.v1
Subject: Biology And Life Sciences, Virology Keywords: Jingmenvirus group; Alongshan virus; qPCR; Flavivirus; Yanggou tick virus; tick-borne viruses
Online: 11 May 2023 (14:25:01 CEST)
The recently discovered Jingmenvirus group includes viruses with a segmented genome, RNA of a positive polarity, and several proteins with distant homology to the proteins of the members of the genus Flavivirus. Some Jingmenvirus group members, namely Alongshan virus (ALSV) and Jingmen tick virus, are reported to be tick-borne human pathogens, causing a wide variety of symptoms. ALSV is widely distributed in Eurasia, yet there is no reliable assay for its detection. Here, we describe a qPCR system for the detection of ALSV. Our data show that this system can detect as low as 104 copies of ALSV in the probe. It shows no amplification with common tick-borne viruses circulating in Eurasia, Yanggou tick virus—another member of the Jingmenvirus group—or some known members of the genus Flavivirus. The qPCR system was tested have no non-specific signal for Ixodes ricinus, I. persulcatus, Dermacentor reticulatus, D. marginatus, Haemaphysalis concinna, and H. japonica ticks. Overall, the qPCR system described here can be used for reliable and quantitative ALSV detection.
ARTICLE | doi:10.20944/preprints202204.0120.v1
Subject: Biology And Life Sciences, Virology Keywords: COVID-19; SARS-CoV-2; Viruses; Omicron BA.1; BA.2; Delta
Online: 13 April 2022 (08:31:45 CEST)
BA.2, a sublineage of Omicron BA.1, is now prominent in many parts of the world. Early reports indicate that BA.2 is more infectious than BA.1. To gain insight into BA.2 mutation profile and the resulting impact of mutations on interaction with receptor and/or monoclonal antibodies, we analyzed available se-quences, structures of Spike/receptor, and Spike/antibody complexes, and conducted molecular dynamics simulations. The results showed that BA.2 has 50 high-prevalent mutations compared to 48 in BA.1. Seventeen BA.1 mutations are not present in BA.2. Instead, BA.2 has 19 unique mutations and a signature Delta variant mutation (G142D). Intriguingly, the BA.2 has 28 signature mutations in Spike, compared to 30 in BA.1. This is due to two revertant mutations S446G and S496G in the receptor-binding domain (RBD), making BA.2 somewhat similar to Wuhan-Hu-1 (WT), which has G446 and G496. The molecular dynamics simulations showed that the RBD consisting of G446/G496 is more stable than S446/S496 containing RBD. Thus, our analyses suggest that BA.2 has evolved with novel mutations (i) to maintain receptor binding similar to WT, (ii) evade the antibody binding greater than BA.1, and (iii) acquire mutation of the Delta variant that may be associated with the high infectivity.
ARTICLE | doi:10.20944/preprints202006.0165.v2
Subject: Biology And Life Sciences, Virology Keywords: Conserved signature indels (CSIs) specific for SARS and SARS-CoV-2-related viruses. Molecular markers distinguishing different clades of Sarbecovirus, Evolutionary relationships between SARS and SARS-CoV-2-related viruses, Origin of SARS-CoV-2 and Pangolin CoV_MP789 viruses, Novel sequence and structural features of spike and nucleocapsid proteins. Genetic recombination.
Online: 26 August 2020 (10:17:16 CEST)
Both SARS-CoV-2 (COVID-19) and SARS coronaviruses (CoVs) are members of the subgenus Sarbecovirus. To understand the origin of SARS-CoV-2, protein sequences from sarbecoviruses were analyzed to identify highly-specific molecular markers consisting of conserved inserts or deletions (termed CSIs) in the spike (S) and nucleocapsid (N) proteins that are specific for either particular clusters/lineages of these viruses or are commonly shared by specific lineages. Three novel CSIs in the N-terminal domain of the spike protein S1-subunit (S1-NTD) are uniquely shared by the SARS-CoV-2, BatCoV-RaTG13 and most pangolin CoVs, distinguishing this cluster of viruses (SARS-CoV-2r) from all others. In the same positions, where these CSIs are found, related CSIs are also present in two other sarbecoviruses (viz. CoVZXC21 and CoVZC45 forming CoVZC cluster), which form an out group of the SARS-CoV-2r cluster. These three CSIs are not found in the SARS-CoVs. However, both SARS and SARS-CoV-2r CoVs contain two large CSIs in the C-terminal domain of S1 (S1-CTD), which binds the human ACE-2 receptor, that are absent in the CoVZC cluster of CoVs. These results indicate that while the S1-NTD of the SARS-CoV-2r viruses possesses the sequence characteristics of the CoVZC cluster of CoVs, their S1-CTD resembles the SARS viruses. Thus, the spike protein of SARS-CoV-2r viruses has likely originated from a recombination event between the S1-NTD of the CoVZC viruses and the S1-CTD of SARS viruses. This inference is also supported by the amino acid sequence similarity of the S1-NTD and S1-CTD from SARS-CoV-2 compared to the CoVZC and SARS CoVs. We also present evidence that one of the pangolin-CoV_MP789, whose receptor-binding domain is most similar to the SARS-CoV-2, is also derived by a recent recombination between the S1-NTD of the CoVZC CoVs and the S1-CTD of a SARS-CoV-2 related virus. Several other identified CSIs are specific for others clusters of sarbecoviruses including a clade consisting of bat SARS-CoVs (BM48-31/BGR/2008 and SARS_BtKY72). Structural mappings studies show that the identified CSIs are located within surface-exposed loops and form distinct patches on the surface of the spike protein. These surface loops/patches are predicted to interact with other host components and play important role in the biology/pathology of SARS-CoV-2 virus. Lastly, the CSIs specific for the SARS-CoV-2r clade provide novel means for development of new diagnostic and therapeutic targets for these viruses.
REVIEW | doi:10.20944/preprints202210.0029.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: host-pathogen interactions; infection; viruses; translation; post-transcriptional modification; transfer RNA; bacteria; archaea
Online: 5 October 2022 (09:47:07 CEST)
Viruses feature an evolutionary shaped minimal genome that is obligately dependent on the cellular transcription and translation machinery for propagation. To suppress host cell immune responses and ensure efficient replication, viruses employ numerous tactics to favor viral gene expression and protein synthesis. This necessitates a carefully balanced network of virus- and host-encoded components, of which the RNA-based regulatory mechanisms have emerged as particularly interesting albeit insufficiently studied, especially in unicellular organisms. Here, recent advances that further our understanding of RNA-based translation regulation, mainly through post-transcriptional chemical modification of ribonucleosides, codon usage, and (virus-encoded) transfer RNAs, will be discussed in the context of viral infection.
ARTICLE | doi:10.20944/preprints202208.0520.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: Multiplex PCR; Real time PCR; Human herpes viruses; clinical significance; Pediatric Leukemia patients
Online: 30 August 2022 (10:30:06 CEST)
Objectives: Human herpes viruses can cause life-threatening diseases in immunocompromised children, especially leukemic patients. Therefore, the aim of this study is to detect the human herpes viruses (HHV1-7) and to investigate its clinical significance in Middle Eastern Pediatric Leukemia Patients by using 2 Independent PCR assays. Methods: Detection of human herpes virus DNA has been done in blood samples of 200 pediatric leukemia patients in addition to 90 blood donors as a control group using multiplex PCR assays. When a ‘‘positive’’ result was observed, real-time PCR was performed to measure the viral load. Results: The most frequent herpes virus infection in Middle Eastern Pediatric Leukemia cases was CMV, followed by EBV, then HHV6, VZV, HHV7, HSV1, and HSV2, where they were 92/200 (46%), 76/200 (38%), 72/200 (36%), 48/200 (24%), 12/200 (6%), 8/200 (4%), and 2/200 (1%) respectively. Also, there was a statistically significance difference between leukemic patients and their controls regarding CMV, EBV, HHV6, and VZV (P <0.05). Correlation between percentage of co-infection, and clinical parameters for the 7 herpes viruses has been studied, and there is an increase in absolute neutrophilic count (ANC), total leukocyte count (TLC) and duration of fever and neutropenia in age group 6-11 years for HHV6/CMV, then in age group 12-18 years especially for EBV/CMV and CMV/HHV6. Also, our results show that multiplex PCR assay is close to single PCR assay in relation to specificity and sensitivity which in turn prove its validity for early diagnosis of herpes viral infection. Conclusions: Adopting multiplex PCR technique is helpful in screening of virus infections. It will save time, effort, cost effective and will assist in rapid diagnosis. However, the clinical relevance of the virus infection needs to be evaluated by quantitative real-time PCR which in turn will help patient's management by using appropriate antiviral treatment.
REVIEW | doi:10.20944/preprints202104.0193.v2
Subject: Biology And Life Sciences, Virology Keywords: SARS-CoV-2; HIV; zoonotic viruses; COVID-19 and AIDS pandemics; viral entry
Online: 8 April 2021 (10:51:11 CEST)
SARS-CoV-2 and HIV are zoonotic viruses that rapidly reached pandemic scale causing global losses and fear. The COVID-19 and AIDS pandemics ignited massive efforts worldwide to develop antiviral strategies and characterize viral architectures, biological and immunological properties, and clinical outcomes. Although both viruses have a comparable appearance as enveloped viruses with positive-stranded RNA and envelope spikes mediating cellular entry, the entry process, downstream biological and immunological pathways, clinical outcomes, and disease courses are strikingly different. This review provides a systemic comparison of both viruses’ structural and functional characteristics delineating their distinct strategies for efficient spread.
REVIEW | doi:10.20944/preprints202101.0184.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Alzheimer’s Disease; antibacterial; anti-biofilm; antifungal; antiviral; bacteria; infectious burden; parasites; pathogens; viruses
Online: 11 January 2021 (11:28:10 CET)
Alzheimer’s disease (AD) is a chronic neurodegenerative disease associated with the overproduction and accumulation of amyloid-β peptide and hyperphosphorylation of tau proteins in the brain. Despite extensive research on the amyloid-based mechanism of AD pathogenesis, the underlying cause of AD remains poorly understood. No disease-modifying therapies currently exist, and numerous clinical trials have failed to demonstrate any benefits. The recent discovery that the amyloid-β peptide has antimicrobial activities supports the possibility of an infectious aetiology of AD and suggests that amyloid-β plaque formation might be induced by infection. AD patients have a weakened blood-brain barrier and immune system and are thus at elevated risk of microbial infections. Such infections can cause chronic neuroinflammation, production of the antimicrobial amyloid-β peptide, and neurodegeneration. Various pathogens, including viruses, bacteria, fungi, and parasites have been associated with AD. Most research in this area has focused on individual pathogens, with herpesviruses and periodontal bacteria being most frequently implicated. The purpose of this review is to highlight the potential role of multi-pathogen infections in AD. Recognition of the potential coexistence of multiple pathogens and biofilms in AD's aetiology may stimulate the development of novel approaches to its diagnosis and treatment. Multiple diagnostic tests could be applied simultaneously to detect major pathogens, followed by anti-microbial treatment using antiviral, antibacterial, antifungal, and anti-biofilm agents.
REVIEW | doi:10.20944/preprints202101.0171.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: microgravity; spaceflight; immunology; pathogens; macrophages; bacteria; viruses; innate immune response; adaptive immune response
Online: 11 January 2021 (09:44:52 CET)
Immune dysfunction has long been reported by medical professionals regarding astronauts suffering from opportunistic infections both during their time in space and a short time period afterwards once back on Earth. Various species of prokaryotes on board these space missions or cultured in a microgravity analogue exhibit increased virulence, enhanced formation of biofilms, and in some cases develop specific resistance for specific antibiotics. This poses a substantial health hazard to the astronauts confined in constant proximity to any present bacterial pathogens on long space missions with a finite number of resources including antibiotics. Furthermore, some bacteria cultured in microgravity develop phenotypes not seen in Earth gravity conditions, providing novel insights into bacterial evolution and research.
REVIEW | doi:10.20944/preprints202007.0613.v3
Subject: Biology And Life Sciences, Virology Keywords: infective dose; SARS-CoV-2; COVID-19; respiratory viruses; viral load; viral dynamics
Online: 7 December 2020 (11:36:05 CET)
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is pandemic. Prevention and control strategies require an improved understanding of SARS-CoV-2 dynamics. We did a rapid review of the literature on SARS-CoV-2 viral dynamics with a focus on infective dose. We sought comparisons of SARS-CoV-2 with other respiratory viruses including SARS-CoV-1 and MERS-CoV. We examined laboratory animal, and human studies. The literature on infective dose, transmission, and routes of exposure was limited specially in humans, and varying endpoints were used for measurement of infection. We propose the minimum infective dose of COVID-19 in humans, is higher than 100 particles, possibly slightly lower than the 700 particles estimated for H1N1 influenza. Despite variability in animal studies, there was some evidence that increased dose at exposure correlated with higher viral load clinically, and severer symptoms. Higher viral load measures did not reflect COVID-19 severity. Aerosol transmission seemed to raise the risk of more severe respiratory complications in animals. An accurate quantitative estimate of the infective dose of SARS-CoV-2 in humans is not currently feasible and needs further research. Further work is also required on the relationship between routes of transmission, infective dose, co-infection, and outcomes.
Subject: Biology And Life Sciences, Virology Keywords: origin of viruses; phylogenetic reconstruction; reductive evolution; obligate intracellular parasites; Varidnaviria; Bamfordvirae; Nucleocytoviricota
Online: 19 September 2020 (03:51:15 CEST)
The extension of virology beyond its traditional medical, veterinary or agricultural applications, now called environmental virology, has shown that viruses are both the most numerous and diverse biological entities on earth. In particular, virus isolation studies involving unicellular eukaryotic hosts (heterotrophic and photosynthetic protozoans) revealed numerous viral types previously unexpected in terms of virion structure and morphology, genome size and gene content, or mode of replication. Complemented by large-scale metagenomic analyzes, these discoveries have rekindled interest in the enigma of the evolutionary origin of viruses, for which no simple definition encompassing all of their diversity is still unanimous. Several laboratories have repeatedly tackled the deep reconstruction of the evolutionary history of viruses, using various methods of molecular phylogeny applied to the few shared genes detected in certain virus groups (e.g. the Nucleocytoviricota). Beyond the practical difficulties of establishing reliable homology relationships from extremely divergent sequences, I present here purely conceptual arguments highlighting several fundamental limitations plaguing the reconstruction of the deep evolutionary history of viruses, and even more the identification of their unique of multiple origin (s). Those limitations are direct consequences of the particularly random mechanisms which govern the reductive evolution of obligate intracellular parasites.
ARTICLE | doi:10.20944/preprints202211.0482.v1
Subject: Biology And Life Sciences, Virology Keywords: Biothermodynamics of viruses; HIV-1; Binding constant; Gibbs energy of binding; Antigen-receptor binding
Online: 25 November 2022 (12:44:38 CET)
HIV-1, like other viruses, represents an open thermodynamic system. This is why it is important to know its thermodynamic properties. Virus-host interactions are performed at the membrane as antigen-receptor binding. Antigen-receptor binding represents a chemical reaction, similar to protein-ligand interactions. The driving force for antigen-receptor binding is Gibbs energy of binding. Knowing Gibbs energy of binding, it is possible to estimate the rate of virus binding and entry into host cells. In this paper, binding equilibrium constants and standard Gibbs energies of binding between the HIV-1 gp120 antigen and the CD4 receptor have been reported at 4°C, 22°C and 37°C.
REVIEW | doi:10.20944/preprints202107.0261.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: self-replicating RNA viruses; vaccines; infectious diseases; cancer; immune response; tumor regression; protection; approval
Online: 12 July 2021 (12:38:49 CEST)
Alphaviruses, flaviviruses, measles viruses and rhabdoviruses are enveloped single-stranded RNA viruses, which have been engineered as expression vector systems for recombinant protein expression and vaccine development. Due to the presence of non-structural genes encoding the replicase complex, a 200,000-fold amplification of viral RNA occurs in the cytoplasm of infected cells providing extreme transgene expression levels, which is why they are named self-replicating RNA viruses. Expression of surface proteins of pathogens causing infectious disease and tumor antigens provide the basis for vaccine development against infectious diseases and cancer. The self-replicating RNA viral vectors can be administered as replicon RNA, recombinant viral particles, or layered DNA/RNA replicons. Self-replicating RNA viral vectors have been applied for vaccine development against influenza virus, HIV, hepatitis B virus, human papilloma virus, Ebola virus and recently coronaviruses, especially SARS-CoV-2 the causative agent of the COVID-19 pandemic. Measles virus and rhabdovirus vector-based SARS-CoV-2 vaccine candidates have been subjected to clinical trials. Moreover, RNA vaccine candidates based on self-amplifying alphaviruses have also been evaluated in clinical settings. Various cancers such as brain, breast, lung, ovarian, prostate cancer and melanoma have also been targeted for vaccine development. Robust immune responses and protection have been demonstrated in animal models. Clinical trials have shown good safety and target-specific immune responses. Ervebo, the VSV-based vaccine against Ebola virus disease has been approved for human use.
REVIEW | doi:10.20944/preprints202107.0064.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: virotherapy; oncolytic viruses; gliomas; pancreatic cancer; adenoviruses; parvoviruses; enteroviruses; blood-brain barrier; tropism; transgene
Online: 2 July 2021 (14:23:22 CEST)
The idea of using the lytic power of viruses against the malignant cells has been entertained for many decades. However, oncolytic viruses (OV) gained broad attention as an emerging anti-cancer therapy only recently with the successful implementation of the oncolytic herpesvirus to treat advanced melanoma. OVs offer an attractive therapeutic combination of tumor-specific cell lysis together with immune stimulation, yet the latter effect is less well studied. Nevertheless, OVs can be envisaged as potential in situ tumor vaccines. The therapeutic potential of OVs can be instigated further by using the molecular biological and biotechnological tools to modify the existing viruses for their optimal tumor selectivity and enhanced immune stimulation. Furthermore, OVs can be readily combined with other therapeutic agents to increase the efficacy of the existing therapeutic schemes. In this review, we discuss biotechnological advances in the development of therapeutic applications of OVs in Russia. Particular emphasis is made on the OV-mediated treatment of glioblastoma. In addition, we highlight the challenges of oncolytic virotherapy, and describe the strategies to optimize current approaches to improve clinical outcomes.
ARTICLE | doi:10.20944/preprints202311.1864.v1
Subject: Biology And Life Sciences, Virology Keywords: SARS-CoV-2; transmission; respiratory; viruses; healthcare; sterilization; air; hamster model; UV-C light; inactivation
Online: 29 November 2023 (10:18:14 CET)
Background: SARS-CoV-2 continues to impact human health globally, with airborne transmission being a significant mode for transmission. In addition to tools like vaccination and testing, counter-measures that reduce viral spread in indoor settings are critical. This study aims to assess the efficacy of UV-C light, utilizing the Violett sterilization device, as a countermeasure against airborne transmission of SARS-CoV-2 in the highly susceptible Golden Syrian hamster model. Methods: Two cohorts of naïve hamsters were subjected to airborne transmission from experimentally infected hamsters; one cohort was exposed to air treated with UV-C sterilization, while the other cohort was exposed to un-treated air. Results: Treatment of air with UV-C light prevented the airborne transmission of SARS-CoV-2 from experimentally exposed hamster to naïve hamsters. Notably, this protection was sustained over a muti-day exposure period during peak viral shedding from hamsters. Conclusion: These findings demonstrate the efficacy of the UV-C light to mitigate airborne SARS-CoV-2 trans-mission. As variants to continue to emerge, UV-C light holds promise as a tool to reduce infections in diverse indoor settings, ranging from healthcare facilities to households. This study reinforces the urgency of implementing innovative methods to reduce airborne disease transmission and safeguard public health against emerging biological threats.
COMMUNICATION | doi:10.20944/preprints202007.0012.v1
Subject: Medicine And Pharmacology, Orthopedics And Sports Medicine Keywords: COVID-19; football; soccer; microbiology; microdroplets; saliva; SARS-CoV-2, sport; soccer; surfaces; transmission; viruses
Online: 3 July 2020 (05:13:30 CEST)
Safely resuming sporting events while the coronavirus is spreading is challenging – yet possible – if the science is taken into account. Two main ways the coronavirus can spread among football players is through air-suspended microdroplets (and possibly aerosols), and via contact with contaminated surfaces. Here we estimated virus survival in dried saliva droplets on a football pitch (i.e., on the grass) and on the ball itself, and compared these measures between mid-day and nighttime matches. We find, based on experiments with the enveloped phage Phi6 – a surrogate for SARS-Cov-2 – that while the virus survives reasonably well on both pitch and ball during a nighttime match (~10% survival), virtually no viruses survived the 90-minute duration of a mid-day match on a hot, sunny day. These results, taken together with studies reporting rapid deactivation of coronavirus in aerosols by sunlight, suggest that playing football in mid-day reduces the likelihood of transmission between players, and thus increases players’ safety.
ARTICLE | doi:10.20944/preprints201912.0172.v1
Subject: Biology And Life Sciences, Virology Keywords: ticks; cattle, rna viruses; next-generation sequencing; phylogeny; microfluidic real-time pcr technology; Caribbean; lips
Online: 12 December 2019 (12:29:36 CET)
Ticks transmit a wide variety of pathogens including bacteria, parasites and viruses. Over the last decade, numerous novel viruses have been described in arthropods, including ticks, and their characterization has provided new insights into RNA virus diversity and evolution. However, little is known about their ability to infect vertebrates. As very few studies have described the diversity of viruses present in ticks from the Caribbean, we implemented an RNA-sequencing approach on Amblyomma variegatum and Rhipicephalus microplus ticks collected from cattle in Guadeloupe and Martinique. Among the viral communities infecting Caribbean ticks, we selected four viruses belonging to the Chuviridae, Phenuiviridae and Flaviviridae families for further characterization and designing antibody screening tests. While viral prevalence in individual tick samples revealed high infection rates, suggesting a high level of exposure of Caribbean cattle to these viruses, no seropositive animals were detected. These results suggest that the Chuviridae- and Phenuiviridae-related viruses identified in the present study are more likely tick endosymbionts, raising the question of the epidemiological significance of their occurrence in ticks, especially regarding their possible impact on tick biology and vector capacity. The characterization of these viruses might open the door to new ways of preventing and controlling tick-borne diseases.
ARTICLE | doi:10.20944/preprints201907.0308.v1
Subject: Medicine And Pharmacology, Pathology And Pathobiology Keywords: orthohantavirus; bunyavirus; VHF; viruses; haemorrhagic fever; epidemiology; infectious diseases; Barbados; Caribbean; virology; incidence; vectors; Americas
Online: 28 July 2019 (11:43:17 CEST)
Analysis of the demographic, temporal and seasonal distribution of hantavirus infections in Barbados was conducted using national surveillance data for 861 laboratory confirmed cases during 2008-2016. The crude incidence rate of hantavirus infections varied from 5.05 to 100.16 per 100,000 persons per year. One major hantavirus epidemic occurred in Barbados during 2010. Hantavirus cases occurred throughout the year with low level transmission during the dry season (December to June) with increased transmission during rainy season (July to November) and a seasonal peak in August. Hantavirus incidence rates were significantly higher in females than males every year during the study period. More than 50% of hantavirus cases were 30 years of age or less. The highest incidence rate (63.36 cases per 100,000 population) was observed among patients 0–4 years of age. This represents the first epidemiological data for hantavirus disease among an entire population in the English-speaking Caribbean.
REVIEW | doi:10.20944/preprints201608.0043.v1
Subject: Biology And Life Sciences, Virology Keywords: enveloped viruses; viral glycoproteins; endoplasmic reticulum-associated degradation; ERAD; unfolded protein response; UPR; ER stress
Online: 4 August 2016 (11:44:59 CEST)
Enveloped viruses represent a significant category of pathogens that cause serious diseases in animals. These viruses express envelope glycoproteins that are singularly important during infection of host cells by mediating fusion between the viral envelope and host cell membranes. Despite low homology at protein levels, three classes of viral fusion proteins have, as of yet, been identified based on structural similarities. Their incorporation into viral particles is dependent upon their proper sub-cellular localization after being expressed and folded properly in the endoplasmic reticulum (ER). However, viral protein expression can cause stress in the ER, and host cells respond to alleviate the ER stress in the form of the unfolded protein response (UPR); the effects of which have been observed potentiating or inhibiting viral infection. One important arm of UPR is to elevate the capacity of the ER-associated protein degradation (ERAD) pathway, which is comprised of host quality control machinery that ensures proper protein folding. In this review, we provide relevant details regarding viral envelope glycoproteins, UPR, ERAD, and their interactions in host cells.
ARTICLE | doi:10.20944/preprints202305.0888.v1
Subject: Public Health And Healthcare, Public, Environmental And Occupational Health Keywords: airborne viruses; epidemic triggering; SARS-CoV2; infectious aerosol transport; long-distance atmospheric transport; epidemic risk assessment
Online: 12 May 2023 (05:11:38 CEST)
In the present work, we investigate the possibility that long-range airborne transport of infectious aerosols could initiate an epidemic outbreak at distances downwind beyond one hundred kilometers. For this, we have developed a simple atmospheric transport box-model which, for a hypothetical case of a COVID-19 outbreak, was compared to a more sophisticated 3-dimensional transport-dispersion model (HYSPLIT) calculation. Coupled with an extended Wells-Riley description of infection airborne spread, it shows that, the very low probability of outdoor transmission can be compensated by high numbers and densities, such as occurs in large cities, of infected and susceptible people in the source upwind and in the target downwind respectively. This may result in the creation of a few primary cases. It is worth pointing out that the probability of being infected remains very small at the individual level. Therefore, this process alone, which depends on population sizes, geography, seasonality and meteorology, can only “trigger” an epidemic which could then spread by the standard infection routes
HYPOTHESIS | doi:10.20944/preprints202106.0125.v2
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: cell fusion; syncytia; cell hybrids; viruses; coronaviruses; SARS-CoV-2; COVID-19; fusogens; blood coagulation cascade; thrombosis, cancer; vaccines; neurological complications
Online: 9 September 2021 (10:54:14 CEST)
A distinctive feature of the SARS-CoV-2 spike protein is its ability to efficiently fuse cells, thus producing syncytia found in COVID-19 patients. This commentary proposes how this ability enables spike to cause COVID-19 complications as well as side effects of COVID-19 vaccines, and suggests how these effects can be prevented..
ARTICLE | doi:10.20944/preprints201711.0198.v2
Subject: Biology And Life Sciences, Virology Keywords: human coronavirus; MERS-CoV; clinical features; upper respiratory tract infections; lower respiratory tract infections; respiratory viruses
Online: 30 January 2018 (09:52:03 CET)
Human coronaviruses cause both upper and lower respiratory tract infections in humans. In 2012 a sixth human coronavirus (hCoV) was isolated from a patient presenting with severe respiratory illness. The 60-year-old man died as a result of renal and respiratory failure after admission to a hospital in Jeddah, Saudi Arabia. The aetiological agent was eventually identified as a coronavirus and designated Middle East respiratory syndrome coronavirus (MERS-CoV). MERS-CoV has now been reported in more than 27 countries across the Middle East, Europe, North Africa and Asia. As of July 2017, 2040 MERS-CoV laboratory confirmed cases, resulting in 712 deaths, were reported globally, with a majority of these cases from the Arabian Peninsula. This review summarises the current understanding of MERS-CoV, with special reference to the (i) genome structure, (ii) clinical features, (iii) diagnosis of infection and (iv) treatment and vaccine development.
CONCEPT PAPER | doi:10.20944/preprints202309.1514.v1
Subject: Physical Sciences, Optics And Photonics Keywords: Photonics; Molecular gates; Localized surface plasmonic resonance (LSPR); porous silica; bio-sensing; microfluidics; respiratory viruses; chemical contaminants
Online: 22 September 2023 (08:28:33 CEST)
This paper presents the concept of a novel adaptable sensing solution currently being developed under the EU Commission founded PHOTONGATE project. This concept will allow to quantify multiple analytes of the same or different nature (chemicals, metals, bacteria, etc.) in a single test with levels of sensitivity and selectivity at/or over those offered by current solutions. PHOTONGATE relies on two core technologies: a bio-chemical technology (molecular gates) which will confer the specificity and, therefore, the capability to be adaptable to the analyte of interest, and which combined with porous substrates will increase the sensitivity, and a photonic technology based on Local Surface Plasmonic Resonance (LSPR) structures serves as transducer for light interaction. Both technologies are in the micron range, facilitating the integration of multiple sensors within a small area (mm²). The concept will be developed for its application in health diagnosis and food safety sectors. It is thought as an easy-to-use modular concept, which will consist of the sensing module, mainly of a microfluidics cartridge that will house the photonic sensor, and a platform for fluidic handling, optical interrogation, and signal processing. The platform will include a new optical concept, fully Europe Union Made, avoiding optical fibers and expensive optical components.
ARTICLE | doi:10.20944/preprints202308.1579.v1
Subject: Biology And Life Sciences, Animal Science, Veterinary Science And Zoology Keywords: highly pathogenic avian influenza A H5N8; clade 22.214.171.124b; Kosovo; domestic poultry; phylogenetic network analysis; viruses; persistent circulation
Online: 22 August 2023 (12:59:41 CEST)
In this study, we report the first outbreak of highly pathogenic avian influenza (HPAI) A H5N8, clade 126.96.36.199b in Kosovo on May 19, 2021. The outbreak consisted of three temporal phases: May–June 2021, September–November 2021, and January–May 2022. In total, 32 backyard and 10 commercial holdings tested positive for the virus, affecting 179,198 poultry. Interestingly, the third and last phase of the outbreak coincided with the massive H5N1 clade 188.8.131.52b epidemic in Europe. Phylogenetic analyses of 28 viral strains from Kosovo revealed that they were closely related to the H5N8 clade 184.108.40.206.b viruses that have been circulating in Albania, Bulgaria, Croatia, Hungary, and Russia in early 2021. Whole genome sequencing of the 25 and partial sequencing of 3 H5N8 viruses from Kosovo showed high nucleotide identity, forming a distinctive cluster and suggesting a single introduction. The results of the network analysis were in accordance with the three epidemic waves and suggested that the viral diffusion could have been caused by secondary spreads among farms and/or different introductions of the same virus from wild birds. The persistent circulation of the same virus over a one-year period highlights the potential risk of the virus becoming endemic, especially in settings with non-adequate biosecurity.
ARTICLE | doi:10.20944/preprints202208.0024.v1
Subject: Biology And Life Sciences, Virology Keywords: highly pathogenic avian influenza viruses; H5N8; H5N5; Clade 220.127.116.11; phylogenetic network analyses; next-generation sequencing; MinION; epidemiology
Online: 1 August 2022 (14:57:42 CEST)
During autumn/winter in 2016 – 2017 and 2020 – 2021, highly pathogenic avian influenza viruses (HPAIV) caused severe outbreaks in Germany and Europe. Multiple clade 18.104.22.168b H5 HPAI subtypes were responsible for increased mortality in wild birds and high mortality and massive losses in the poultry sector. To clarify putative entry sources and delineate interconnections between outbreaks in poultry holdings and wild birds, we applied whole-genome sequencing and phylodynamic analyses combined with the results of epidemiological outbreak investigations. Varying outbreak dynamics of the distinct reassortants allowed for the identification of individual, putatively wild bird-mediated entries into backyard holdings, several clusters comprising poultry holdings, local virus circulation for several weeks, direct farm-to-farm transmission and potential reassortment within a turkey holding with subsequent spill-over of the novel reassorted virus into the wild bird population. Whole-genome sequencing allowed for allowed for a unique high-resolution molecular epidemiology analysis of HPAIV H5Nx outbreaks, recommended to be used as a standard tool. The presented detailed account of the genetic, temporal and geographical characteristics of the recent German HPAI H5Nx situation emphasizes the role of poultry holdings as an important source of novel genetic variants and reassortants.
CASE REPORT | doi:10.20944/preprints202106.0311.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: Honey bees; Apis mellifera; acaricides; pesticides; Toxic Unit; Varroa destructor; Nosema ceranae; bee viruses; tau-fluvalinate; coumaphos
Online: 11 June 2021 (09:55:42 CEST)
In this Case Report we analyze the possible causes of the poor health status of a professional Apis mellifera iberiensis apiary located in Gajanejos (Guadalajara, Spain). Several factors that potentially favor colony collapse were identified, including Nosema ceranae infection, alone or in combination with other factors (eg, BQCV and DWV infection), and the accumulation of acaricides commonly used to control Varroa destructor in the beebread (coumaphos and tau-fluvalinate). Based on the levels of residues, the average toxic unit estimated for the apiary, suggests a possible increase in vulnerability to infection by N. ceranae due to the presence of high levels of acaricides. These data highlight the importance of evaluating these factors in future monitoring programs, as well as the need to adopt adequate preventive measures as part of national and international welfare programs aimed at guaranteeing the health and fitness of bees.
ARTICLE | doi:10.20944/preprints202005.0471.v2
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: DNA oligomers; harmonic progression; hyperbolic rules; matrices; tensor product; quantum informatics; oligomer sums method; genomes; genes; viruses; proteins; long Russian texts; phonetic sequences
Online: 21 June 2020 (15:26:04 CEST)
The author's method of oligomer sums for analysis of oligomer compositions of eukaryotic and prokaryotic genomes is described. The use of this method revealed the existence of general rules for cooperative oligomeric organization of a wide list of genomes. These rules are called hyperbolic because they are associated with hyperbolic sequences including the harmonic progression 1, 1/2, 1/3, .., 1/n. These rules are demonstrated by examples of quantitative analysis of many genomes from the human genome to the genomes of archaea and bacteria. The hyperbolic (harmonic) rules, speaking about the existence of algebraic invariants in full genomic sequences, are considered as candidates for the role of universal rules for the cooperative organization of genomes. The described phenomenological results were obtained as consequences of the previously published author's quantum-information model of long DNA sequences. The oligomer sums method was also applied to the analysis of long genes and viruses including the COVID-19 virus; this revealed, in characteristics of many of them, the phenomenon of such rhythmically repeating deviations from model hyperbolic sequences, which are associated with DNA triplets. In addition, an application of the oligomer sums method are shown to the analysis of the following long sequences: 1) amino acid sequences in long proteins like the protein Titin; 2) phonetic sequences of long Russan literary texts (for checking of thoughts of many authors that phonetic organization of human languages is deeply connected with the genetic language). The topics of the algebraic harmony in living bodies and of the quantum-information approach in biology are discussed.
REVIEW | doi:10.20944/preprints201909.0212.v1
Subject: Biology And Life Sciences, Virology Keywords: positive-sense single-stranded rna viruses; innate immune evasion; type 1 interferon; viral pathogenesis; type 3 interferon
Online: 18 September 2019 (17:12:01 CEST)
Positive-sense single-stranded RNA (+ssRNA) viruses comprise many (re-)emerging human pathogens that pose a public health problem. Our innate immune system and in particular the interferon response form the important first line of defense against these viruses. Given their genetic flexibility, these viruses have therefore developed multiple strategies to evade the innate immune response in order to optimize their replication capacity. Already many molecular mechanisms of innate immune evasion by +ssRNA viruses have been identified. However, research addressing the effect of host innate immune evasion on the pathology caused by the viral infection is less prevalent in literature, though very relevant and interesting. Since interferons have been implicated in inflammatory diseases and immunopathology in addition to their protective role in infection, the influence of antagonizing the immune response may have an ambiguous effect on the clinical outcome of the viral disease. Therefore, this review discusses what is currently known about the role of interferons and host immune evasion in the pathogenesis of emerging viruses belonging to the coronaviruses, alphaviruses and flaviviruses.
COMMUNICATION | doi:10.20944/preprints202311.1394.v1
Subject: Biology And Life Sciences, Virology Keywords: RNA secondary structure; RNA viruses; connectivity table; WUSS; hairpin loop; internal loop; bulge; multifurcation loop; external loop; stem
Online: 22 November 2023 (14:54:28 CET)
Recent advancements in experimental and computational methods for RNA secondary structure detection have revealed the crucial role of RNA structural elements in diverse molecular processes within living cells. It has been demonstrated that the secondary structure of the entire viral genome is often responsible for performing crucial functions in the viral life cycle and also influences virus evolution. To investigate the role of viral RNA secondary structure, alongside experimental techniques, the use of bioinformatics tools is important for analyzing various secondary structure patterns, including hairpin loops, internal loops, multifurcations, external loops, bulges, stems, and pseudoknots. Here, we have introduced a Python package for analyzing RNA secondary structure elements in viral genomes, which includes the recognition of common secondary structure patterns, the generation of descriptive statistics for these structural elements, and the provision of their basic properties. We applied the developed package to analyze the secondary structures of complete viral genomes collected from the literature, aiming to gain insights into viral function and evolution. Both the package and the collection of secondary structures of viral genomes are available at http://github.com/KazanovLab/RNAsselem.
SHORT NOTE | doi:10.20944/preprints202303.0553.v2
Subject: Public Health And Healthcare, Public, Environmental And Occupational Health Keywords: A(H5N1) avian influenza virus; Influenza viruses; Virus host range; Zoonotic risk, Human exposure risk; Viral infection; Epidemiology
Online: 4 April 2023 (14:22:33 CEST)
A brief overview of the past and present trajectories made by the A(H5N1) avian influenza virus among domestic birds, avian and mammalian wildlife species and humans is presented here, thereby taking into special account the 22.214.171.124b clade of the virus recently emerged in several geographic areas of the globe.
ARTICLE | doi:10.20944/preprints202306.0194.v1
Subject: Biology And Life Sciences, Virology Keywords: insect viruses; arthropod virus; distant homology detection; remote homology detection; virulence factor; tospovirus; structure prediction; cypovirus; small protrusion domain
Online: 2 June 2023 (11:45:35 CEST)
Today, the most powerful approach to detect distant homologs of a protein is based on structure prediction and comparison. Yet this approach is still inapplicable to many viral proteins. Therefore, we developed a powerful sequence-based procedure to identify distant homologs of viral proteins. It relies on 3 main principles: 1) Traces of sequence similarity with a protein can persist beyond the significance cutoff of homology detection programs; 2) Candidate homologs can be identified among proteins with weak sequence similarity to the query, by using "contextual" information, e.g. taxonomy or type of host infected; 3) These candidate homologs can be validated using highly sensitive profile-profile comparison.As a test case, we applied our approach to a protein without known homologs, ORF4 of Lake Sinai virus (which infects bees). We discovered that ORF4 is composed of a domain that has homologs in proteins from >20 taxa of viruses infecting arthropods. We called it “Widespread, Intriguing, Versatile” (WIV) domain because it is found in proteins with a wide variety of domain organizations and functions. For example, WIV is encoded by the NSs protein of tospoviruses, a global threat to food security, which infect plants through arthropod vectors; by the protein encoded by RNA2 ORF1 of chronic bee paralysis virus, a widespread virus of bees; and by various proteins of cypoviruses, which infect the silkworm bombyx mori. WIV has a previously unknown structural fold, according to Alphafold predictions. In some viral species, WIV facilitates infection of arthropods, according to bibliographical evidence
REVIEW | doi:10.20944/preprints202303.0112.v1
Subject: Biology And Life Sciences, Virology Keywords: Viruses; Escherichia coli; Klebsiella aerogenes; Candida utilis; Gibbs energy of biosynthesis; Bi-osynthesis reaction; Enthalpy; Entropy; Pathogen-host interaction
Online: 6 March 2023 (15:47:22 CET)
Pathogen-host interaction (virus-host, bacteria-host and fungi-host) is analyzed from the perspective of biothermodynamics. A mechanistic model of pathogen-host interactions, which was earlier applied to virus-host interactions, was applied for the first time to bacteria-host and fungi-host interactions. Through a mechanistic model suggested in this research, it is possible to explain the phenomenon of tropism of microorganisms to develop infections in certain tissues. Gibbs energy of biosynthesis represents the driving force for growth of bacteria inside host organisms. A growing bacterial colony represents a thermodynamic system, while the host organism is its surroundings. The permissiveness coefficient determines the possibility of growth of bacteria in an appropriate environment (tissue).
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: coronavirus; COVID-19; Hepatitis C Virus (HCV); Human Immunodeficiency Virus (HIV); Influenza viruses ribonucleic acid (RNA); SARS-CoV-2
Online: 19 February 2021 (14:34:38 CET)
Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is the etiological agent of the current pandemic worldwide. The pathological condition induced by this pathogen is known as COVID-19 disease. SARS-CoV-2 associated pandemic has been defined as a “public health emergency of international concern” by the International Health Regulation Emergency Committee of the World Health Organization. To date, considerable efforts are in progress to develop more advanced strategies against SARS-CoV-2. Despite the numerous scientific studies published, our knowledge regarding this pathogen is still incomplete, as this virus has been identified only recently. Therefore, scientific investigation of the SARS-CoV-2 has been possible only for a short period of time and effective management of the serious forms of this disease is still lacking. Considerable efforts are in progress worldwide with the purpose to develop more advanced strategies against this pathogen. In this review, we have analyzed the structural and the biological SARS-CoV-2 characteristics and those of other well-known RNA viruses, with the aim to identify possible similarities and analogies between all these pathogens, may be a very useful approach. These infectious agents have been widely studied since several years ago and, a large series of scientific reports are available in the literature regarding this topic. Therefore, focusing on the Human Immunodeficiency Virus (HIV), Hepatitis C Virus (HCV) and Influenza viruses (IVs), we have collected their historical data, clinical manifestations, pathogenetic mechanisms and related infections. Taking advantage of the results of our research, we have assembled this narrative review, with the aim to get useful insights and lessons from HIV, HCV and IVs characteristics and, consequently, to transfer the obtained knowledge to the study of SARS-CoV-2 biology. There are well known differences between all these pathogens. In particular, they present a distinct mode of transmission, as SARS-CoV-2 and Influenza viruses are airborne pathogens, whereas HIV and HCV are bloodborne infectious agents. However, these viruses exhibit some potential common clinical manifestations and pathogenetic mechanisms and their understanding may contribute to establishing preventive measures and new therapies against SARS-CoV-2. Accordingly, we have analysed and discussed the following points: 1) the biology, the pathogenesis and the clinical manifestations of SARS-CoV-2, HIV, HCV and IVs in mankind; 2) the onset and spreading of pandemics caused by respiratory viruses according to a perspective historical point of view; 3) the possible development of a persistent SARS-CoV-2 reservoir worldwide; 4) the possibility of SARS-CoV-2 reinfection/reactivation; 5) the possible involvement and impact of climatic factors in increasing the risk of SARS-CoV-2 spreading.
REVIEW | doi:10.20944/preprints202112.0525.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: colorectal cancer; immunotherapy; checkpoint blockade; adoptive cell therapy; monoclonal antibodies; oncolytic viruses; anti-cancer vaccines; cytokine; T cell; NK cell
Online: 31 December 2021 (15:14:39 CET)
Though early-stage colorectal cancer has a high 5-year survival rate of 65-92% depending on the specific stage, this probability drops to 13% after the cancer metastasizes. Frontline treatments for colorectal cancer such as chemotherapy and radiation often produce dose-limiting toxicities in patients and acquired resistance in cancer cells. Additional targeted treatments are needed to improve patient outcomes and quality of life. Immunotherapy involves treatment with peptides, cells, antibodies, viruses, or small molecules to engage or train the immune system to kill cancer cells. Preclinical and clinical investigations of immunotherapy for treatment of colorectal cancer including immune checkpoint blockade, adoptive cell therapy, monoclonal antibodies, oncolytic viruses, anti-cancer vaccines, and immune system modulators have been promising, but demonstrate limitations for patients with proficient mismatch repair enzymes. In this review, we discuss preclinical and clinical studies investigating immunotherapy for treatment of colorectal cancer and predictive biomarkers for response to these treatments. We also consider open questions including optimal combination treatments to maximize efficacy, minimize toxicity, and prevent acquired resistance and approaches to sensitize mismatch repair proficient patients to immunotherapy.
ARTICLE | doi:10.20944/preprints202002.0114.v1
Subject: Biology And Life Sciences, Virology Keywords: Jingmen tick virus; Alongshan virus; flavi-like viruses; class II viral fusion proteins; O-liked glycans; mucin-like domain; virus evolution
Online: 9 February 2020 (17:29:14 CET)
Jingmen viruses are newly described segmented flavi-like viruses that have a worldwide distribution in ticks and have been associated with febrile illnesses in humans. Computational analyses were used to predict that Jingmen flavi-like virus glycoproteins have structural features of class II viral fusion proteins, including an ectodomain consisting of beta-sheets and short alpha-helices, a fusion peptide with interfacial hydrophobicity and a three domain architecture. Jingmen flavi-like virus glycoproteins have a sequence enriched in serine, threonine and proline at the amino terminus, which is a feature of mucin-like domains. Several of the serines and threonines are predicted be modified by the addition of O-linked glycans. Some of the glycoproteins are predicted to have an additional mucin-like domain located prior to the transmembrane anchor, whereas others are predicted to have a stem consisting of two alpha-helices. The flavivirus envelope protein and Jingmen flavi-virus glycoproteins may have diverged from a common class II precursor glycoprotein with a mucin-like domain or domains acquired after divergence.
ARTICLE | doi:10.20944/preprints202106.0020.v1
Subject: Biology And Life Sciences, Virology Keywords: Vesicular Stomatitis; Herpes Simplex; Yellow Fever; Animal Viruses; Plaque Assay; Real-time; Live Cell Imaging, Automated Image Analysis; DNA Fluorescent Dyes, Antiviral Screening
Online: 1 June 2021 (10:40:37 CEST)
Conventional plaque assays rely on the use of overlays to restrict viral infection allowing the formation of distinct foci that grow in time as the replication cycle continues leading to counta-ble plaques that are visualized with standard techniques such as crystal violet, neutral red or immunolabeling. This classical approach takes several days until large enough plaques can be visualized and counted with some variation due to subjectivity in plaque recognition. Since plaques are clonal lesions produced by virus-induced cytopathic effect, we applied DNA fluores-cent dyes with differential cell permeability to visualize them by live cell imaging. We could observe different stages of that cytopathic effect corresponding to an early wave of cells with chromatin-condensation followed by a wave of dead cells with membrane permeabilization within plaques generated by different animal viruses. This approach enables an automated plaque identification using image analysis to increase single plaque resolution compared to crystal violet counterstaining and allows its application to plaque tracking and plaque reduction assays to test compounds for both antiviral and cytotoxic activities. This fluorescent real-time plaque assay sums to those next-generation technologies by combining this robust classical method with modern fluorescence microscopy and image analysis approaches for future applica-tions in virology.
ARTICLE | doi:10.20944/preprints202205.0234.v1
Subject: Biology And Life Sciences, Biophysics Keywords: SARS-CoV-2; COVID-19; virions mass balance; spatial modelling of toxics concentrations; human exposure to airborne substances; Substance Flow Analysis (SFA); environmental routes of toxic viruses; primary production of SARS-2 virions
Online: 17 May 2022 (14:19:43 CEST)
Measures in the SARS-CoV-2 pandemic were based on rough ideas regarding transmission routes of pathogens. Quantified models of physical transmission routes are mostly lacking, a gap to be filled. Vaccines and medicines, important, are not studied here. We first survey main routes, from primary production in the alveoli and intestines to emissions, environmental routes, to exposure and alveolar infection. Next, specific routes are modelled, mostly at a preliminary state, open to systematic improvement. Starting from a standardized emitter, modelling results show extreme differences in potential exposure, in a range covering up to 4 orders of magnitude. The outcomes are pathogen-specific, already different between SARS-CoV-2 and influenza. Extreme exposures may result in smaller spaces; with lower ventilation rates; with a high density of emitting persons per m3; who stay there for several hours; and visitors staying more than a few minutes. In spaces where a build-up of concentrations is low, exposures are low, lowest in open air situations. A main conclusion for the next pandemic is that a quantified model can give strong guidance on where measures are primarily due. For SARS-CoV-2, ventilation can be improved short-term. Longer-term, effective ventilation rules and adaptation of buildings may reduce high exposures substantially.
ARTICLE | doi:10.20944/preprints202105.0490.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Breast cancer infection; breast cancer immunity; breast cancer virus; genome biochemistry; nasopharyngeal cancer; herpes viruses; hereditary breast cancer; BRCA1; BRCA2; Burkitt's lymphoma; homologous recombination; DNA repair; viral cancer; chromosome breaks; Breast cancer infection; breast cancer immunity; breast cancer virus; nasopharyngeal cancer; hereditary breast cancer; BRCA1; BRCA2; Burkitt's lymphoma
Online: 20 May 2021 (12:43:11 CEST)
Inherited mutations in BRCA1 and BRCA2 genes increase risks for breast, ovarian, and other cancers. Both genes encode proteins for accurately repairing chromosome breaks. If mutations inactivate this function, chromosome fragments may not be restored correctly. Resulting chromosome rearrangements can become critical breast cancer drivers. Because I had data from thousands of cancer structural alterations that matched viral infections, I wondered whether infections contribute to chromosome breaks and rearrangements in hereditary breast cancers. There are currently no interventions to prevent chromosome breaks because they are thought to be unavoidable. However, if chromosome breaks come from infections, they can be treated or prevented. I used bioinformatic analyses to test publicly available breast cancer sequence data around chromosome breaks for DNA similarity to all known viruses. Human DNA flanking breakpoints usually had the strongest matches to Epstein-Barr virus (EBV) tumor variants HKHD40 and HKNPC60. Many breakpoints were near sites that anchor EBV genomes, human EBV tumor-like sequences, EBV-associated epigenetic marks, and fragile sites. On chromosome 2, sequences near EBV genome anchor sites accounted for 90% of breakpoints (p<0.0001). On chromosome 4, 51/52 inter-chromosomal breakpoints were close to EBV-like sequences. Five EBV genome anchor sites were near breast cancer breakpoints at precisely defined, disparate gene or LINE locations. Breakpoint flanking regions resembled known EBV-cancers. Twenty-five breakpoints in breast cancers were within 1.25% of EBV cancer breakpoints. In addition to BRCA1 or BRCA2 mutations, all the breast cancers had mutated genes essential for immune responses. Because of this immune compromise, herpes viruses can activate and produce nucleases that break chromosomes. Alternatively, anchored viral episomes can obstruct break repairs, whatever the cause. The results, therefore, imply proactive treatment and prevention of herpes viral infections may prevent some chromosome breaks and benefit BRCA mutation carriers.